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General Information
Symbol
Dmel\w
Species
D. melanogaster
Name
white
Annotation Symbol
CG2759
Feature Type
FlyBase ID
FBgn0003996
Gene Model Status
Stock Availability
Enzyme Name (EC)
Adenosinetriphosphatase (3.6.1.3)
ABC-type guanine transporter (7.6.2.6)
Gene Snapshot
white (w) encodes a member of the ABCG2 class of transporters, transporting molecules such as cyclic GMP, biogenic amines and pigments including drosopterins and ommochromes. Mutation of w results in viable flies with white eyes. A shortened version of the gene (mini-w) has been widely used in transformation constructs as a selectable marker. [Date last reviewed: 2019-03-21]
Also Known As

EG:BACN33B1.1 , DMWHITE, mini-white

Key Links
Genomic Location
Cytogenetic map
Sequence location
X:2,790,599..2,796,466 [-]
Recombination map

1-1.5

RefSeq locus
NC_004354 REGION:2790599..2796466
Sequence
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
GO Summary Ribbons
Protein Family (UniProt)
Belongs to the ABC transporter superfamily. ABCG family. Eye pigment precursor importer (TC 3.A.1.204) subfamily. (P10090)
Catalytic Activity (EC)
Experimental Evidence
ATP + H(2)O + guanine(Side 1) = ADP + phosphate + guanine(Side 2) (7.6.2.6)
Predictions / Assertions
ATP + H(2)O = ADP + phosphate (3.6.1.3)
Summaries
Gene Group (FlyBase)
ABCG ATP-BINDING CASSETTE TRANSPORTER SUBFAMILY -
The ATP-binding cassette (ABC) transporter family are primary active transporters that use ATP hydrolysis to drive the transport of substrates across the membrane. In metazoans the ABCG subfamily are half transporters. Half transporters must dimerize to form a functional transporter. (Adapted from FBrf0224053).
Protein Function (UniProtKB)
Part of a membrane-spanning permease system necessary for the transport of pigment precursors into pigment cells responsible for eye color. White dimerize with brown for the transport of guanine. Scarlet and white complex transports a metabolic intermediate (such as 3-hydroxy kynurenine) from the cytoplasm into the pigment granules.
(UniProt, P10090)
Phenotypic Description (Red Book; Lindsley and Zimm 1992)
*e(g): enhancer of garnet
Apparently wild type but, in combination with g, produces a more orange eye than g alone. RK3.
w: white
The white locus is involved in the production and distribution of ommochrome (brown) and pteridine (red) pigments found in the compound eyes and ocelli of adult flies as well as the pigments in adult testis sheaths and larval Malpighian tubules; the specific function of the protein it encodes is still unknown, but it is believed to be a membrane-associated ATP-binding transport protein for pigment precursors in both the ommochrome and pteridine pathways (Sullivan and Sullivan, 1975; Mount, 1987; Dreesen et al., 1988; Tearle et al., 1989). w1 was the first mutant found in Drosophila melanogaster (Morgan, 1910; Morgan and Bridges, 1916). Mutant alleles do not appreciably affect the viability and fertility of the flies. Extreme white alleles as well as white deficiencies remove both brown and red pigments, the w1 allele having very little, if any, pteridine (Hadorn and Mitchell, 1951); isoxanthopterin is present in considerable quantity during pupation but is eliminated during the first three days of adult life (Hadorn, 1954, Experientia 10: 483-84). Hypomorphic alleles are visibly lighter in combination with w1 than when present as homozygotes. Intermediate white alleles result in partial loss of ommochromes and pteridines; some alleles also affect the distribution of these pigments in the compound eyes (Lewis, 1956; Green, 1959a, 1959c). Although the mutants are positively phototactic, they show no optomotor responses (Kalmus, 1943, J. Genet. 45: 206-13). Wild-type alleles are incompletely dominant over mutant alleles, w/w+ heterozygotes, though visibly indistinguishable from w+/w+, have less red pigment (Muller, 1935; Ziegler-Gunder and Hadorn, 1958; Green, 1959b). Mutant larval disks transplanted into wild-type host develop autonomously (Beadle and Ephrussi, 1936). Early genetic studies identified mutations separable by intralocus recombination into at least seven groups spanning 0.03 cm (Lewis, 1952; MacKendrick and Pontecorvo, 1952; Green, 1959a; Judd, 1959). Mutants occupying the centromere-proximal sites apparently play a regulatory role (Judd, 1976). Subsequent molecular analysis has localized the proximal mutations to the 5' end of the transcription unit (we) and the upstream flanking sequences (wsp) (Judd, 1987). Mutations at the distal sites have been mapped to the protein coding exons and the introns between them. The proximally-located regulatory mutants (we, for example) do not show dosage compensation; they suppress the zeste gene, and some of them (the wsp alleles) affect the distribution of the red and brown screening pigments of the eyes. Most of the distally-located structural mutants show dosage compensation, wa/Y males having the same eye color as wa/wa females, and do not suppress (but may interact with) zeste. Green (1959a) found that wi fails to show dosage compensation and does not suppress zeste; but wh exhibits both zeste suppression and dosage compensation. In spite of their heterogeneity, the alleles at the white locus fail to complement each other except for wsp which partially complements all other w alleles except in the presence of za [Babu and Bhat, 1980, Development and Neurobiology of Drosophila, (Siddiqi, Babu, Hall, and Hall, eds.). Plenum Press, New York and London, pp. 35-40)]. Some white alleles (wc for example) are extremely unstable (Green, 1976); w1 is slightly unstable, giving rise to we and wh, mutants with darker eyes than w1. The locus is characterized by asymmetrical recombination involving transposons; the mutants wr,def and wr,dup are the result of such exchange (Davis et al., 1987). Some P-element white transformations show reproducible patterns of pigmentation which can be altered by the trans-acting gene zeste (Rubin et al., 1985).
wm: white-mottled
There are many w alleles that show variegated eye color. The wm mutants most commonly used for variegation studies are wm4 and wm264-58. In these alleles, extra heterochromatin partially suppresses eye mottling (Gowen and Gay, 1933, Proc. Nat. Acad. Sci. USA 19: 122-26; Koliantz, Hartmann-Goldstein, and Fuller, 1984, Heredity 52: 203-13; Koliantz and Hartmann-Goldstein, 1984, Heredity 53: 215-22; Baker and Spofford, 1959, Univ. Texas Publ. 5914: 135-54; Spofford, 1959, Proc. Nat. Acad. Sci. USA 45: 1003-07). In wm264-58, variegation less (more wild-type in color) in homozygous females than in heterozygous females. Color variegation found in the testis-sheath as well as the eyes of wm264-58 male flies (Baker, 1968, Adv. Genet. 14: 133-169). In some lines, less variegation when paternally inherited; in others, less variegation when maternally inherited or no parental effect. Mottling in wm4 and wm4h is enhanced by E(var)7 and E(var)c101 (Reuter and Wolff, 1981, Mol. Gen. Genet. 182: 516-19); mottling in wm4 and wm264-58 is suppressed by Su(var) (Spofford, 1962, Genetics 47: 986-87) and a number of other suppressor mutations (Reuter and Wolff, 1981).
wa: white-apricot
Placed on the genetic map of white to the right of wbf and the left of wch. The amount of pigment formed by wa is a function of gene dose: wa/- female < wa/Y male = wa/wa female < wa/wa/wa female < wa/wa male (Muller, 1932). A wa optic disk transplanted into a wild-type host shows autonomous eye color development (Beadle and Ephrussi, 1936). Deficiencies and duplications for wa can be produced as a result of nonhomologous exchanges within the white region. wa gives rise to partial revertants, as wr (Muller), waM (Mossige), and wa57i (Green). Eye color is modified in certain mutant combinations. wa;bw is slightly lighter than wa. wa;st is light pinkish yellow (Mainx, 1938) as is wa v. z wa is lighter than either mutant alone, only slightly darker than wbf (Green, 1959a). wa rb and wa g have nearly white eyes; wa wch, wbf wa, and wa in combination with su(f) all have white eyes. su(wa) wa and su(wa)G wa have browner eyes than wa. The triple mutant su(wa) wa su(f) has eyes only slightly lighter than wa (Levis et al., 1984). wBwx wa is like wa (Judd). wa/+ has lighter eyes than +/+ in v homozygotes (Braver, 1953); Tp(2;3)P darkens wa. Transpositions of wa and the neighboring gene rst+ have been isolated at more than 120 sites in the genome [Ising and Ramel, 1976, The Genetics and Biology of Drosophila (Ashburner and Novitski, eds.). Academic Press, London, New York, San Francisco, Vol. 1b, pp. 947-54].
wbf: white-buff
Occupies a recombination site between wBwx and wa (Judd, 1959). Spontaneous reversions reported by Redfield (1952, DIS 26: 28). wbf; st has white eyes (Mainx, 1938, Z. Indukt. Abstamm. Vererbungsl. 75: 256-76). Eyes of wbf rb and wbf g are lighter than the eyes of wbf, rb, or g (Green, 1959a).
wbl: white-blood
Located distal to w (MacKendrick and Pontecorvo, 1952) and we (Judd, 1958; Green, 1959a). At 19, eye color as dark as pn; at 30, as light as wbf or wi; sensitivity greatest 40-48 hr after pupation (Ephrussi and Herold, 1945, Genetics 30: 62-70).
wBwx: white-Brownex
Located distal to wbf (Judd, 1957, 1959). Reduces recombination in the y-spl interval. Heterozygotes between wBwx and other white alleles or deficiencies are indistinguishable in eye color from wBwx/wBwx. The double mutant wBwx wcol is lighter than either single mutant, but wBwx/wa and wBwx/wbf are indistinguishable from wa and wbf, respectively.
wc: white-crimson
Maps at the same site as wa. Derivatives of wc may be stable (w+ for example) or mutable (such as wdc and wdi) and include both point mutations and deficiencies (Green, 1967, Genetics 56: 467-82). The mutations take place in both males and females, may occur in clusters, and do not appear to involve recombination. Transpositions of a segment of the w gene that includes wc to different locations on the third chromosome have been recovered and are mutable (Green, 1969, Genetics 61: 423-28; Green, 1976).
wcf: white-coffee
Located near wBwx and just distal to wa (Welshons and Nicoletti, 1963, DIS 38: 80). Females heterozygous for wcf and w, wa, wco, wch, wbl, wcol, or wsat have eye color of wcf homozygous females. wcf/+ flies wild-type.
wch: white-cherry
Occupies site proximal to wa and distal to wsp (Lewis, 1956). Eyes light in double mutant with rb or g, white with wa. Enhanced by P and e(we); suppressed by Su(wch), making eyes brownish (Rasmuson, 1970, Hereditas 65: 83-96).
wco: white-coral
Located distal to w1 (MacKendrick and Pontecorvo, 1952). Enhanced by e(we); lightens rb and g (Green, 1959a). wco;st has yellow eyes (Mainx, 1938).
wDZL: white-Dominant-zeste-like
wDZL is located in or immediately proximal to the rightmost set of previously-defined white mutant sites (Bingham, 1981). While this mutant affects the pigmentation of the eyes, it has no effect on the color of the larval Malpighian tubules or the testis sheath of adult males. wDZL shows synapsis-dependent dominance over w+. It is a highly mutable allele (like wc), giving rise spontaneously to w+ and w- derivatives with a frequency of 0.5-1.5%. Interactions between wDZL and z are summarized in the allele table. It was observed that, when carrying the wild-type allele of z, wDZL/w- females have brown eyes; with z1, however, hemizygous wDZL females have yellow eyes (Bingham, 1980, Genetics 95: 341-53).
we: white-eosin
Placed proximal to wa (Green, 1959a). Amount of pigment formed by we not a function of gene dose: we female = we male < we/we male = we/we female < we/we/we female (Muller, 1932). Mutant enhanced by P, cru, and whg as well as by E(we). Lightens rb and g (Green, 1959a). A we optic disk transplanted into a wild-type host shows autonomous eye color development (Beadle and Ephrussi, 1936).
wi: white-ivory
Placed on the genetic map distal to w1 (MacKendrick, 1953, DIS 27: 100). wi is unstable, reverting spontaneously to w+ with a frequency of 5x10-5 in wi/wi females and 5x10-6 in wi/Y males and wi/Df(1)w females (Lewis, 1959, Genetics 44: 522; Bowman, 1965, Genetics 52: 1069-79). The frequency of germinal reversions and of somatic reversions in larval eye tissue is increased by X rays (Lewis, 1959; Bowman and Green, 1964, Genetics 50: 237). No dosage compensation shown by the mutant (Green 1959a). Recombination between flanking w alleles reduced in wi, but restored in its revertants (Bowman, 1965; Bowman and Green, 1966, Genetica 37: 7-16).
wsp: white-spotted
Located proximal to wch and distal to wDZL. wsp affects that deposition of the eye pigments, resulting in a variegated phenotype, but does not affect the pigmentation of the larval Malpiphian tubules. Testis pigmentation varies with different alleles, wsp3 males having unpigmented testes, but wsp1 and wsp2 males showing enhanced testis pigmentation (Davison et al., 1985; Pirrotta, Stellar, and Bozzetti, 1985, EMBO J. 4: 3501-08; Judd, 1987). Partial complementation occurs between wsp alleles and certain other w mutations when they are synapsed; for example, wsp/w, wsp/wch, and wsp/wa females have homogeneous brown eyes (Green, 1959a). The double mutants wa wsp and wch wsp have white and pale yellow eyes, respectively. wsp, when heterozygous with a deficiency for all or part of the w locus, produces a phenotype like that of wsp homozygotes (Green, 1959c). In the presence of z1, two synapsed copies of wsp in trans (or tandemly repeated) result in yellow-eyed females; z1 females with one copy of wsp have wild-type eye color. A specific regulator of the wsp eye phenotype, su(wsp), has been isolated as a partial revertant of wsp1 (Chapman and Bingham, 1985); this suppressor restores wild-type eye color to wsp1, wsp2, wsp3, and wsp4 flies, but not to the wsp81d mutant (Davison et al., 1985).
wzm: white-zeste mottled
wzm is located to the right of wa and to the left of w1. It is an unstable white allele, mutating to derivatives, most of which are unstable (Judd, 1963, Proc. Int. Congr. Genet. 11th, Vol. 1: 3-4; 1964, DIS 39: 60). Since all z+ wzm males (as well as z+ wzm/z+ wzm females) have wild-type eye color, the mutant z was used as an indicator of the mutability of wzm strains. Derivatives of wzm (Kalisch and Becker, 1970, Mol. Gen. Genet. 107: 321-35) include wzl (from the z wzm stock), wzmz (from the z wzm stock), and wzmzrb, wzmzz and wzmzw (from the z wzmz stock). Only wzl is stable. The mutants were often recovered in clusters. wzmz reverts to wzm+ (eye color between z wzm and z w+) and the white-eyed wzmzz and ww. Other derivatives (wz, wzh, wzs) were recovered by Judd (1957; 1969, Genetics 61: s29).
Summary (Interactive Fly)

ABC transporter of amines that partners with Brown in determination of eye pigmentation - Behavioral abnormalities in , and mutants could arise from reduced amine levels in neurons

Gene Model and Products
Number of Transcripts
1
Number of Unique Polypeptides
1

Please see the GBrowse view of Dmel\w or the JBrowse view of Dmel\w for information on other features

To submit a correction to a gene model please use the Contact FlyBase form

Protein Domains (via Pfam)
Isoform displayed:
Pfam protein domains
InterPro name
classification
start
end
Protein Domains (via SMART)
Isoform displayed:
SMART protein domains
InterPro name
classification
start
end
Comments on Gene Model

Gene model reviewed during 5.45

Sequence Ontology: Class of Gene
Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0070490
2352
687
Additional Transcript Data and Comments
Reported size (kB)

8.0, 7.9, 2.6 (northern blot)

5.7, 2.6, 1.75 (northern blot)

2.212 (sequence analysis)

Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
RefSeq ID
GenBank
FBpp0070468
75.7
687
8.76
Polypeptides with Identical Sequences

There is only one protein coding transcript and one polypeptide associated with this gene

Additional Polypeptide Data and Comments
Reported size (kDa)
Comments
External Data
Subunit Structure (UniProtKB)

Heterodimer of white with either brown or scarlet.

(UniProt, P10090)
Linkouts
Sequences Consistent with the Gene Model
Mapped Features

Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\w using the Feature Mapper tool.

External Data
Crossreferences
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Linkouts
Gene Ontology (23 terms)
Molecular Function (7 terms)
Terms Based on Experimental Evidence (4 terms)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
inferred from electronic annotation with InterPro:IPR003439, InterPro:IPR017871
(assigned by InterPro )
inferred from electronic annotation with InterPro:IPR003439, InterPro:IPR017871
(assigned by InterPro )
inferred from biological aspect of ancestor with PANTHER:PTN000443718
(assigned by GO_Central )
Biological Process (12 terms)
Terms Based on Experimental Evidence (11 terms)
CV Term
Evidence
References
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from genetic interaction with FLYBASE:e; FB:FBgn0000527
inferred from genetic interaction with FLYBASE:t; FB:FBgn0086367
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000443718
(assigned by GO_Central )
Cellular Component (4 terms)
Terms Based on Experimental Evidence (3 terms)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000443718
(assigned by GO_Central )
Expression Data
Expression Summary Ribbons
Colored tiles in ribbon indicate that expression data has been curated by FlyBase for that anatomical location. Colorless tiles indicate that there is no curated data for that location.
For complete stage-specific expression data, view the modENCODE Development RNA-Seq section under High-Throughput Expression below.
Transcript Expression
No Assay Recorded
Stage
Tissue/Position (including subcellular localization)
Reference
mutational analysis
Stage
Tissue/Position (including subcellular localization)
Reference
northern blot
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data

Microarray data shows w gene expression highest in Malpighian tubules (from FlyAtlas).

Adult males express the 2.6kb wa transcript at about twice the level of females.

The 2.6kb w transcript is greatly reduced in abundance in wa. Levels of the 2.6kb transcript are further reduced with increasing doses of E(wa).

Levels of the 1.75 kb transcript of wa decrease stepwise with increasing doses of E(wa).

E(wa) increases the levels of the aberrant 5.7 kb mRNA from wa.

Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
immunolocalization
Stage
Tissue/Position (including subcellular localization)
Reference
mass spectroscopy
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data

w is detected in retina and in the lamina. In the eye, the signal is concentrated in primary pigment cells with some signal in photoreceptors. In the lamina, signal is observed in the epithelial glial cells.

Marker for
 
Subcellular Localization
CV Term
Evidence
References
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

GBrowse - Visual display of RNA-Seq signals

View Dmel\w in GBrowse 2
RNA-Seq by Region - Search RNA-Seq expression levels by exon or genomic region
Reference
See Gelbart and Emmert, 2013 for analysis details and data files for all genes.
Developmental Proteome: Life Cycle
Developmental Proteome: Embryogenesis
External Data and Images
Linkouts
FLIGHT - Cell culture data for RNAi and other high-throughput technologies
FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
Flygut - An atlas of the Drosophila adult midgut
Images
Alleles, Insertions, and Transgenic Constructs
Classical and Insertion Alleles ( 1017 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 481 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of w
Transgenic constructs containing regulatory region of w
Deletions and Duplications ( 313 )
Disrupted in
Duplicated in
Not disrupted in
Phenotypes
For more details about a specific phenotype click on the relevant allele symbol.
Lethality
Allele
Sterility
Allele
Other Phenotypes
Allele
Phenotype manifest in
Allele
Orthologs
Human Orthologs (via DIOPT v7.1)
Homo sapiens (Human) (17)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
8 of 15
Yes
Yes
6 of 15
No
No
5 of 15
No
No
4 of 15
No
Yes
2 of 15
No
No
1 of 15
No
No
 
1 of 15
No
No
 
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Model Organism Orthologs (via DIOPT v7.1)
Mus musculus (laboratory mouse) (22)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
9 of 15
Yes
Yes
6 of 15
No
No
5 of 15
No
No
4 of 15
No
Yes
4 of 15
No
Yes
2 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Rattus norvegicus (Norway rat) (24)
7 of 13
Yes
Yes
5 of 13
No
No
4 of 13
No
No
4 of 13
No
No
3 of 13
No
Yes
2 of 13
No
Yes
2 of 13
No
Yes
2 of 13
No
No
2 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
Yes
1 of 13
No
Yes
Xenopus tropicalis (Western clawed frog) (12)
4 of 12
Yes
Yes
3 of 12
No
No
2 of 12
No
Yes
2 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
Danio rerio (Zebrafish) (15)
6 of 15
Yes
Yes
5 of 15
No
No
5 of 15
No
Yes
5 of 15
No
No
5 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
No
2 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Caenorhabditis elegans (Nematode, roundworm) (17)
12 of 15
Yes
Yes
9 of 15
No
Yes
8 of 15
No
Yes
7 of 15
No
No
6 of 15
No
No
6 of 15
No
Yes
6 of 15
No
No
4 of 15
No
No
2 of 15
No
No
2 of 15
No
Yes
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Arabidopsis thaliana (thale-cress) (37)
5 of 9
Yes
Yes
4 of 9
No
No
4 of 9
No
No
4 of 9
No
No
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
Yes
3 of 9
No
No
3 of 9
No
Yes
3 of 9
No
No
3 of 9
No
No
2 of 9
No
No
2 of 9
No
No
2 of 9
No
No
2 of 9
No
Yes
2 of 9
No
No
2 of 9
No
Yes
2 of 9
No
Yes
1 of 9
No
No
1 of 9
No
Yes
1 of 9
No
No
1 of 9
No
No
1 of 9
No
Yes
1 of 9
No
No
1 of 9
No
No
1 of 9
No
Yes
1 of 9
No
No
1 of 9
No
No
1 of 9
No
Yes
1 of 9
No
Yes
1 of 9
No
No
Saccharomyces cerevisiae (Brewer's yeast) (10)
9 of 15
Yes
Yes
8 of 15
No
Yes
7 of 15
No
Yes
7 of 15
No
Yes
7 of 15
No
Yes
6 of 15
No
Yes
5 of 15
No
Yes
5 of 15
No
Yes
5 of 15
No
No
4 of 15
No
Yes
Schizosaccharomyces pombe (Fission yeast) (2)
5 of 12
Yes
Yes
4 of 12
No
Yes
Orthologs in Drosophila Species (via OrthoDB v9.1) ( EOG0919044K )
Organism
Common Name
Gene
AAA Syntenic Ortholog
Multiple Dmel Genes in this Orthologous Group
Drosophila suzukii
Spotted wing Drosophila
Drosophila simulans
Drosophila simulans
Drosophila sechellia
Drosophila erecta
Drosophila yakuba
Drosophila ananassae
Drosophila pseudoobscura pseudoobscura
Drosophila persimilis
Drosophila persimilis
Drosophila persimilis
Drosophila willistoni
Drosophila virilis
Drosophila mojavensis
Drosophila grimshawi
Orthologs in non-Drosophila Dipterans (via OrthoDB v9.1) ( EOG09150300 )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Musca domestica
House fly
Glossina morsitans
Tsetse fly
Lucilia cuprina
Australian sheep blowfly
Mayetiola destructor
Hessian fly
Aedes aegypti
Yellow fever mosquito
Anopheles darlingi
American malaria mosquito
Culex quinquefasciatus
Southern house mosquito
Orthologs in non-Dipteran Insects (via OrthoDB v9.1) ( EOG090W0A7O )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Bombyx mori
Silkmoth
Bombyx mori
Silkmoth
Bombyx mori
Silkmoth
Danaus plexippus
Monarch butterfly
Danaus plexippus
Monarch butterfly
Danaus plexippus
Monarch butterfly
Heliconius melpomene
Postman butterfly
Heliconius melpomene
Postman butterfly
Apis florea
Little honeybee
Apis florea
Little honeybee
Apis mellifera
Western honey bee
Apis mellifera
Western honey bee
Apis mellifera
Western honey bee
Bombus impatiens
Common eastern bumble bee
Bombus impatiens
Common eastern bumble bee
Bombus impatiens
Common eastern bumble bee
Bombus terrestris
Buff-tailed bumblebee
Bombus terrestris
Buff-tailed bumblebee
Linepithema humile
Argentine ant
Linepithema humile
Argentine ant
Megachile rotundata
Alfalfa leafcutting bee
Megachile rotundata
Alfalfa leafcutting bee
Nasonia vitripennis
Parasitic wasp
Dendroctonus ponderosae
Mountain pine beetle
Tribolium castaneum
Red flour beetle
Tribolium castaneum
Red flour beetle
Pediculus humanus
Human body louse
Pediculus humanus
Human body louse
Rhodnius prolixus
Kissing bug
Rhodnius prolixus
Kissing bug
Rhodnius prolixus
Kissing bug
Rhodnius prolixus
Kissing bug
Cimex lectularius
Bed bug
Cimex lectularius
Bed bug
Cimex lectularius
Bed bug
Cimex lectularius
Bed bug
Cimex lectularius
Bed bug
Cimex lectularius
Bed bug
Cimex lectularius
Bed bug
Acyrthosiphon pisum
Pea aphid
Acyrthosiphon pisum
Pea aphid
Acyrthosiphon pisum
Pea aphid
Acyrthosiphon pisum
Pea aphid
Acyrthosiphon pisum
Pea aphid
Zootermopsis nevadensis
Nevada dampwood termite
Zootermopsis nevadensis
Nevada dampwood termite
Zootermopsis nevadensis
Nevada dampwood termite
Orthologs in non-Insect Arthropods (via OrthoDB v9.1) ( EOG090X0A3M )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strigamia maritima
European centipede
Strigamia maritima
European centipede
Stegodyphus mimosarum
African social velvet spider
Stegodyphus mimosarum
African social velvet spider
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Daphnia pulex
Water flea
Orthologs in non-Arthropod Metazoa (via OrthoDB v9.1) ( EOG091G05L3 )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strongylocentrotus purpuratus
Purple sea urchin
Strongylocentrotus purpuratus
Purple sea urchin
Strongylocentrotus purpuratus
Purple sea urchin
Strongylocentrotus purpuratus
Purple sea urchin
Ciona intestinalis
Vase tunicate
Ciona intestinalis
Vase tunicate
Paralogs
Paralogs (via DIOPT v7.1)
Drosophila melanogaster (Fruit fly) (28)
6 of 10
6 of 10
5 of 10
5 of 10
5 of 10
5 of 10
5 of 10
4 of 10
4 of 10
4 of 10
4 of 10
4 of 10
4 of 10
4 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
1 of 10
Human Disease Associations
FlyBase Human Disease Model Reports
    Disease Model Summary Ribbon
    Disease Ontology (DO) Annotations
    Models Based on Experimental Evidence ( 0 )
    Allele
    Disease
    Evidence
    References
    Potential Models Based on Orthology ( 2 )
    Human Ortholog
    Disease
    Evidence
    References
    Modifiers Based on Experimental Evidence ( 0 )
    Allele
    Disease
    Interaction
    References
    Disease Associations of Human Orthologs (via DIOPT v7.1 and OMIM)
    Note that ortholog calls supported by only 1 or 2 algorithms (DIOPT score < 3) are not shown.
    Functional Complementation Data
    Functional complementation data is computed by FlyBase using a combination of the orthology data obtained from DIOPT and OrthoDB and the allele-level genetic interaction data curated from the literature.
    Interactions
    Summary of Physical Interactions
    esyN Network Diagram
    Show neighbor-neighbor interactions:
    Select Layout:
    Legend:
    Protein
    RNA
    Selected Interactor(s)
    Interactions Browser

    Please see the Physical Interaction reports below for full details
    RNA-protein
    Physical Interaction
    Assay
    References
    Summary of Genetic Interactions
    esyN Network Diagram
    esyN Network Key:
    Suppression
    Enhancement

    Please look at the allele data for full details of the genetic interactions
    Starting gene(s)
    Interaction type
    Interacting gene(s)
    Reference
    suppressible
    suppressible
    enhanceable
    enhanceable
    enhanceable
    enhanceable
    suppressible
    enhanceable
    suppressible
    enhanceable
    enhanceable
    Starting gene(s)
    Interaction type
    Interacting gene(s)
    Reference
    suppressible
    External Data
    Subunit Structure (UniProtKB)
    Heterodimer of white with either brown or scarlet.
    (UniProt, P10090 )
    Linkouts
    BioGRID - A database of protein and genetic interactions.
    DroID - A comprehensive database of gene and protein interactions.
    InterologFinder - Protein-protein interactions (PPI) from both known and predicted PPI data sets.
    MIST (genetic) - An integrated Molecular Interaction Database
    MIST (protein-protein) - An integrated Molecular Interaction Database
    Pathways
    Signaling Pathways (FlyBase)
    Metabolic Pathways
    External Data
    Linkouts
    Genomic Location and Detailed Mapping Data
    Chromosome (arm)
    X
    Recombination map

    1-1.5

    Cytogenetic map
    Sequence location
    X:2,790,599..2,796,466 [-]
    FlyBase Computed Cytological Location
    Cytogenetic map
    Evidence for location
    3B6-3B6
    Limits computationally determined from genome sequence between P{EP}EP1362 and P{EP}dncEP1395
    Experimentally Determined Cytological Location
    Cytogenetic map
    Notes
    References
    3C2-3C2
    (determined by in situ hybridisation)
    3C-3C
    (determined by in situ hybridisation)
    3B2-3C2
    (determined by in situ hybridisation)
    3C1-3C2
    (determined by in situ hybridisation)
    Experimentally Determined Recombination Data
    Notes

    wcf2 maps in the far left portion of the w locus, 0.019 map units from w1 and wh.

    Alleles wdp and wdp2 map to the left of wch.

    Stocks and Reagents
    Stocks (67,885)
    101196
    101227
    105757
    105759
    105762
    107303
    Genomic Clones (16)
     

    Please Note FlyBase no longer curates genomic clone accessions so this list may not be complete

    cDNA Clones (5)
     

    Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see GBrowse for alignment of the cDNAs and ESTs to the gene model.

    cDNA clones, fully sequences
    BDGP DGC clones
      Other clones
      Drosophila Genomics Resource Center cDNA clones

      For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.

      cDNA Clones, End Sequenced (ESTs)
      BDGP DGC clones
      RNAi and Array Information
      Linkouts
      DRSC - Results frm RNAi screens
      GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
      Antibody Information
      Laboratory Generated Antibodies
       
      Commercially Available Antibodies
       
      Other Information
      Relationship to Other Genes
      Source for database identify of

      Source for identity of: w CG2759

      Source for database merge of

      Source for merge of: w e(g)

      Additional comments
      Other Comments

      The visual acuity of w mutant males is impaired, but their abnormal courtship behaviour in daylight largely results from an overflow of light.

      The absence, or insufficient levels, of extra-retinal w protein increases the sexual arousal of males in general, of which the enhanced male-male courtship, observed in both chaining and single-courtship assays, may be an indirect effect.

      w function is required for the courtship disinhibition seen in wild-type males upon repeated exposure to ethanol.

      Both enhancer-activated and basal w transcription can be silenced by Pc-G proteins at a large number of chromosomal locations.

      w protein is located in the membranes of pigment granules within pigment cells and retinula cells of the eye. No evidence of its presence in the plasma membrane has been seen.

      P-element insertions containing the Mcp-element and mediating pairing sensitive silencing of w expression are subject to long distance silencing interactions with other similar inserts. This occurs in cis or in trans. This effect is strongest between nearest neighbours, and weakens as the distance between the partners increase. Addition of more than two elements does not interfere with the silencing effect. The long distance regulatory activity of the Mcp element can be enhanced by placing it in a mini-w transgene which is flanked by scs and scs'.

      Expression of the y and w genes is sensitive to the level of e(y)1 expression.

      PEV operating on insertions of the w-containing P{hsp26-pt-T} reflects specialised packaging due to heterochromatin proteins that are associated with sequences that can be, but are not necessarily, repetitive.

      The P{FRT(RS3).y}10A insertion, which shows variegation for w expression, reveals imprinted control of gene activity in Drosophila.

      The somatic w/w+ assay has been used to study the genotoxic effects of several structurally related 2B compounds.

      Heterochromatic cluster containing Stellate repeats, cause PEV of a reporter mini-w gene.

      Ufo interacts with w and mutant analysis suggests Ufo affects transposable element insertions. The normal regulatory configuration at w is required for a response. Ufo does not affect the mechanism of position effect variegation.

      A transgene array can cause silencing not only of the w reporter genes within the array but also of a vital gene near the array. The size of the array inducing the effect correlates with the frequency of gene silencing. The repeat arrays behave like natural heterochromatin: increased silencing of a transgene array results from rearrangements that place the array more proximal to pericentric heterochromatin, arrays as small as three copies are sensitive to long-range effects of interactions with heterochromatin in both cis and trans, the array is capable of silencing a non-variegating w transgene on a homologue. Essential gene(s) in the 50C region is silenced by the presence of a variegation P{lacW} array.

      The w gene P-element mediated gene conversion system demonstrates that sufficient homology is required to induced a high number of targeting events.

      Study of the wi assay reveals it is not recommended as a general screening test because the background reversion frequencies show high variability among solvents.

      The Scer\FLP1-Scer\FRT site-specific recombination system can be used to integrate DNA at a chromosomal Scer\FRT target site. Events are recovered using a w reporter gene.

      Copies of the w gene carried in P-elements are capable of trans-inactivation, i.e. can silence the w gene on the paired homolog. Many genes, in many positions of the genome, can sense the heterochromatic state of a paired homologue.

      Genotoxic activation of hydrazine, two symmetrical dialkylhydrazines and ethylene thiourea is evaluated by means of the w/w+ somatic assay in insecticide resistant and insecticide susceptible strains. The susceptible strain is more susceptible to toxicity than the resistant strain.

      The w+mW.hs mutation carried in the P{FRT(whs)} element can be excised from its site of integration by the induction of Scer\FLP1 synthesis. Scer\FLP1 can be used to excise an Scer\FRT-flanked gene after cell division has ceased and the gene, now present on an extrachromosomal circle, is expressed. Most position effects are reverted by the removal of this gene from the chromosome.

      Analysis of 6 spontaneous and 73 γ ray-induced w mutations reveals that on the chromosomal and genetic levels all spontaneous mutations show themselves to be point mutations.

      Mow changes the expression of w. Alterations in the w structural gene and in a specific cis-regulatory domain are unable to block interaction with Mow mutations but those lacking dosage compensation do block Mow interaction. Mutations of Mow can suppress position effect variegation of w (In(1)wm4h).

      One of a class of genes with TATA-less promoters that have a subset of the conserved DPE sequence.

      The w/w+ somatic recombination assay has been carried out in 6 different Drosophila strains using the compounds menadione and paraquat.

      Measurements of the frequency of site specific recombination between P-element-borne w alleles on homologous chromosomes shows that structural heterozygosity inhibits the pairing of alleles that lie distal to a rearrangement breakpoint. Variations in cell cycle length can explain different extents of transvection effects in different tissues. Cells with a longer cell cycle have more time to establish the normal pairing relationships that have been restored by rearrangements. Minute mutations, which slow the rate of cell division, partially restore a transvection effect that is disrupted by an inversion breakpoint.

      The spectrum of genotoxic events detected by the wing somatic mutation and recombination test (SMART) and the wi eye spot test is different. The wi eye spot test appears not to detect mitotic recombination the way the wing spot test does.

      The autosomal "FLP-DFS" technique (using the P{ovoD1-18} P{FRT(whs)} P{hsFLP} chromosomes) has been used to study the zygotic lethal mutation.

      In the presence of a P1\cre transgene driven by a dual Hsp70-Dmau\mariner\T promoter, a w reporter gene flanked by P1\loxP sites is excised with virtually 100% efficiency both in somatic and germ cells. A strong maternal effect, resulting from P1\cre recombinase present in the oocyte, is observed as white or mosaic eye colour in F1 progeny. Excision in germ cells of the F1 yields a strong grand-maternal effect, observed as a highly skewed ratio of eye-colour phenotypes in the F2 generation.

      Position effect variegation appears to have little effect on overall accessibility to Ecol\dam methylase.

      The relative biological effectiveness of 252Cf neutrons has been determined for two different types of somatic mutations, the wing-spot test (using mwh and flr) and reversion of eye-colour (using w).

      Three assays (z-w, wi and wing spot) are used to evaluate the genotoxic response of five chemicals classified as genotoxic non-carcinogens, chemicals significantly increase the frequency of mutant clones.

      Eye mosaic test is used to evaluate the genotoxicity of polychlorinated biphenyls (PCBs).

      The wi somatic assay allows detection of genotoxic agents which induce loss of a tandem duplication.

      Amorphic mutations of z are strong recessive enhancers of position effect variegation (PEV) for the w, rst and N loci. w locus repression by z1 can be reversed by rearrangements that result in the unpairing of the two w alleles.

      Sequences contained in a pb minigene are capable of suppressing a w marker located in a P-element vector. Regions of pb have been identified that are able to repress w gene in a manner that is sensitive to homolog pairing, pairing sensitive (PS) regions.

      Full dosage compensation of the w gene requires both the X chromosome environment and multiple dosage compensation elements, some near the promoter and some in the coding region.

      Dosage compensation of autosomally integrated mini-w genes flanked by gypsy\su(Hw)BR sequences is greatly improved compared to insertions not flanked by gypsy\su(Hw)BR, such that complete or nearly complete compensation was observed at the majority of X and autosomal insertion sites. The su(Hw) protein is essential for this enhanced dosage compensation. gypsy\su(Hw)BR may protect the mini-w gene from a negative autosomal chromatin environment. su(Hw) mutations do not affect dosage compensation of the endogenous w gene.

      The w marker gene of P{lacW} has been used in silencer trap experiments to identify genomic sites that have silencer activity.

      Mis-expression of w in mature males causes a marked change in their sexual behaviour inducing male-male courtship. Most males participate forming male-male courtship chains, circles and lariats. When exposed to an active homosexual courtship environment non-transformant males alter their behaviour and actively participate in male-male chaining. These results demonstrate both genetic and environmental factors play a role in male sexual behaviour.

      The w/w+ somatic mutation and recombination test (SMART) is an in vivo system that is able to reveal genotoxicity of promutagens that are difficult to detect with in vitro genotoxicity test systems.

      The response of the wi system to ten carcinogens is assayed.

      P-element induced chromosome breakage is repaired six times more frequently when a homologous template is located anywhere on the X chromosome than on an autosome. This cis-advantage can operate over more than 15Mb of DNA.

      5' splice site mutation of w can be suppressed by compensatory mutations in the 5' end of U1, both molecularly in transformed cells and phenotypically in transformed flies.

      Eye w/w+ SMART assay is used to study the effect of ethanol pretreatment on X-ray-induced mitotic recombination in females: ethanol does not modify the frequency of white spots.

      Eye w/w+ somatic assay is used to study the activity of the aromatic amines 0-AN, O-TA, 2,4-DAA, 4-NoPDA and 4,4'-ODA in a wild type strain and in an insecticide resistant stock.

      A w/w+ somatic recombination assay has been used to examine four drugs (streptozotocin, metronidazole, griseofulvin and sterigmatocystin) for genotoxic activity.

      w locus confers protective action against X ray damage, resulting in a reduced frequency of dominant lethals. There is at least one genetic factor, located near w, which is responsible for the adaptive response (AR). The AR can be induced by a minimal dose of 0.2mGy, increasing the conditioning dose does not influence the response.

      Ligation mediated PCR procedure has been used to quantitate the accessibility of restriction sites in the chromatin fibre in both the active and inactivated forms of w. Inactivation is not accompanied by substantial change in the accessibility of the chromatin fibre.

      Standard w/w+ assay is used to assay the effect of the antineoplastic agent fotemustine in germ cells.

      At the DNA sequence level D.melanogaster populations from Zimbabwe are more than twice as variable as populations from U.S.A. Most variants are not shared between the two geographic regions and areas of low recombination rates have mutations that are nearly fixed.

      In vitro splicing in both human and Drosophila cell nuclear extracts has been used to investigate the signals required for the splicing of a small intron.

      The male Sxl exon is subject to Sxl regulation when a fragment containing the exon plus flanking intron sequences is placed in the introns of two different genes, ftz and w.

      A test locus for investigating site-specific mutagenesis using the I-element.

      P-element mobilization has been to study the repair of double strand breaks in the white locus in premeiotic germ cells: distribution of conversion tracts is unaffected by changes in the length of sequence homology between the broken ends of the template, indicating that only a short match is required, and frequency of repair is highly sensitive to single base mismatches in the homologous region.

      The w/w+ eye mosaic assay has been used to study genetic heterogeneity in response to genotoxic carcinogens requiring metabolic conversion in seven different strains of Drosophila.

      Phenotypic variation of the genetic components underlying oviposition behaviour is analysed using the complete diallel mating design.

      Several regions of the genome that act as dosage-dependent modifiers of w alleles have been identified.

      The effects of 181 chemicals in the w/w+ assay, which measures genetic damage in somatic cells after treatment of larvae, have been analysed.

      An oligomer of 50bp can mediate base replacement in the vicinity of a P-element in the w gene.

      Alleles of w respond to dosage compensation in metafemales (3X;2A) as a continum of the male and female responses.

      Mutations of y strongly enhance the effect of z mutations on w expression.

      Superunstable mutations generated in crosses of π2 strain to a wa strain or its derivatives. Each superunstable mutation gives rise to a large family of new super-unstable mutations with a wide range of phenotypic expression. Mutations with the same phenotype often differ in the specificity of their potential for further mutation. Each superunstable mutation is associated with a specific, "paired", reversible mutation. Active transposase encoded by P elements is necessary to maintain superinstability. X transposable element is also implicated in the mutability system.

      Transcriptional analysis of wa demonstrates that the w promoter and the copia promoter are not coordinate in their dosage compensation abilities when assayed in larvae and adults in different genomic locations.

      Mutations at white locus have no effect on rate of degeneration of rhabdomeres R1-6 in the time span where ninaE mutations do have an effect.

      Chromatographic and autoradiographic analysis of GTP cyclohydrolase uptake of excised pupal eyes demonstrate that the site of action of the w gene in pteridine synthesis is located in an intracellular site, not in the plasma membrane as previously hypothesised.

      Molecular analysis has identified z binding sites in the eye, but not the testes, enhancer of the w gene. Overlap of these sites is responsible for the z-w interaction. The w promoter is internal to the transcription start site.

      The unstable z-w assay was used to compare mutation rates in germinal and somatic cells. Formaldehyde and methylmethane sulphonate induce mutations in larval and adult feeding in somatic and germinal cells: methylmethane sulphonate causes an elevated frequency of mutations in somatic and germinal cells and formaldehyde only causes somatic mutations.

      z-w assay is highly sensitive to carcinogenic compounds.

      The Inr-a regulatory gene interacts with the white locus via regulatory sequences.

      Genotoxicity of acrolein is investigated using SMART, SCLT (sex chromosome loss test) and SLRLT (sex linked recessive lethal test). Acrolein is mutagenic in SLRLT when injected but not fed, SCLT does not reveal a clastogenic effect with acrolein and acrolein has a genotoxic effect in SMART.

      Recombination of the nucleolus organiser region (NO) by X chromosome inversion onto the In(1)wm51b and In(1)wm4 chromosomes evokes w variegation.

      SMART (somatic mutation and recombination test) has been used to assay the effects of tannic acid alone and in combination with chemical genotoxins and γ-radiation on mutation in D.melanogaster.

      Lesions in w reduce or eliminate pigmentation in the eyes and ocelli and block pigmentation of the fat body and tubules. w is required for the synthesis of ommochrome in any tissue and is involved in the transport of pigmentation precursors.

      The somatic mutation and recombination test (SMART) has been used to assay the genotoxic activity of a number of polycyclic aromatic hydrocarbons.

      Removal of UV-induced pyrimidine dimers is measured in genes ade3, N and w in two diploid immortalised cell lines (Kc and SL2) to investigate whether preferential repair forms part of DNA excision repair. Data supports the idea that preferential repair is not restricted to transcriptionally active sequences.

      The effects of 4 anti-cancer drugs have been assayed in the wi somatic mutation test.

      The rate of precise P-element loss from the w locus under a variety of genetic conditions has been studied.

      A number of super-unstable mutations at the w locus, derived from strains carrying unstable mutations at the oc locus, have been studied.

      Some mutations in w are due to insertion of a Stalker element.

      The effects of larval age and increasing the number of copies of wi on somatic reversion in the wi somatic mutation test has been studied.

      Modification of eye colour in z1 genotypes is independent of a specific w allele.

      Relative success of mutant w and wild type males is frequency-dependent, if the sex ratio is 1:1. If the number of females is constant, this success depends on the ratio between mutant and wild type males. The sex ratio changes strongly affect the male mating activity of both genotypes.

      Only 2 out of 36 ethyl nitrosourea (ENU) induced alleles at the w locus show an alteration of the normal restriction enzyme pattern, suggesting that most of the ENU-induced mutations are due to very small rearrangements, or, most likely, base-pair changes.

      Initiation of transcription at the white promoter is increased by E(wa).

      A w cDNA has been cloned and sequenced.

      Mutations at the mw, su(f), su(wa), E(wa) and Doa loci modify the wa phenotype. They were examined in two way combinations to determine if their effects are additive or epistatic.

      P{Δ2-3}, in conjunction with P{CaSpeR}, induces recombination in the male germ line. Recombination appears to be premeiotic in a high proportion of cases. P{Δ2-3}-P{CaSpeR} combination also elevates the incidence of somatic recombination.

      Ultrastructure and Ca-sequestering properties of eye colour pigment granules (PGs) are studied in the eyes of wild type and mutant flies. A new type of ommochrome PG localises in primary pigment cells and basal terminals of the processes of Semper cells. At room temperature these PGs exhibit OsO4-dependent structural ability. X ray microanalysis revealed a less Ca-binding ability of the PGs as compared to those in secondary pigment cells.

      Similarity of w and st mutant phenotypes may reflect a common biochemical function for the w and st gene products.

      In situ hybridisation of recombinant DNA probes to polytene chromosomes of D.melanogaster and D.virilis is performed to study homologies between the chromosomal Muller elements of the two species.

      The w locus is surrounded by a critical domain that influences the zeste-white interaction proximally and distally. The domain has cis and/or trans-acting functions. There is no evidence of a physical boundary site delimiting the breakage sensitive zeste-white interaction.

      Mutant alleles are useful as markers in clonal analysis.

      The spotted region of the w locus is 590-1270bp 5' to the transcription start site. Mutational analysis demonstrates that the region has two distinct cis-acting regulatory elements and a third element mapping 3' at -670bp.

      Sequence elements present in the region from 1.1 to 1.9kb upstream from the 5' end of the w transcript are required for expression of w in the testes and interaction of w with z.

      Different parts of the 1.8kb region preceding the transcription start of w are required for the expression of the gene in different tissues and at different developmental stages. Sequences required for dosage compensation are contained between -216 and the transcription start site. Another sequence >1080bp upstream of the transcription start is required for the z interaction.

      Temperature sensitive period of w expression is 3-4 days before eclosion, heat induction at this period causes a large number of dark red spots in an orange red background.

      P-element mediated transformation reveals that all genetic information specified by the w+ locus is contained within a 12kb segment of DNA.

      Novel class of w mutations have been selected and analyzed.

      Regulation of the w gene locus has been studied using P element mediated transformation and in vitro mutagenesis. A 3.4kb segment of the w locus gives no detectable phenotypic expression.

      The white locus is involved in the production and distribution of ommochrome (brown) and pteridine (red) pigments found in the compound eyes and ocelli of adult flies as well as the pigments in adult testis sheaths and larval Malpighian tubules; the specific function of the protein it encodes is still unknown, but it is believed to be a membrane-associated ATP-binding transport protein for pigment precursors in both the ommochrome and pteridine pathways (Sullivan and Sullivan, 1975; Mount, 1987; Dreesen, Johnson and Henikoff, 1988; Tearle, Belote, McKeown, Baker and Howells, 1989). w1 was the first BLUFF mutant found in D.melanogaster (Morgan, 1910; Morgan and Bridges, 1916). Mutant alleles do not appreciably affect the viability and fertility of the flies. Extreme white alleles as well as white deficiencies remove both brown and red pigments, the w1 allele having very little, if any, pteridine (Hadorn and Mitchell, 1951); isoxanthopterin is present in considerable quantity during pupation but is eliminated during the first three days of adult life (Hadorn, 1954). Hypomorphic alleles are visibly lighter in combination with w1 than when present as homozygotes. Intermediate white alleles result in partial loss of ommochromes and pteridines; some alleles also affect the distribution of these pigments in the compound eyes (Lewis, 1956; Green, 1959a; Green, 1959c). Although the mutants are positively phototactic, they show no optomotor responses (Kalmus, 1943). Wild-type alleles are incompletely dominant over mutant alleles, w/w+ heterozygotes, though visibly indistinguishable from w+/w+, have less red pigment (Muller, 1935; Ziegler-Gunder and Hadorn, 1958; Green, 1959b). Mutant larval discs transplanted into wild-type host develop autonomously (Beadle and Ephrussi, 1936). Early genetic studies identified mutations separable by intralocus recombination into at least seven groups spanning 0.03 cm (Lewis, 1952; MacKendrick and Pontecorvo, 1952; Green, 1959a; Judd, 1959). Mutants occupying the centromere-proximal sites apparently play a regulatory role (Judd, 1976). Subsequent molecular analysis has localized the proximal mutations to the 5' end of the transcription unit (we) and the upstream flanking sequences (wsp1) (Judd, 1987). Mutations at the distal sites have been mapped to the protein coding exons and the introns between them. The proximally-located regulatory mutants (we, for example) do not show dosage compensation; they suppress the zeste gene and some of them (the wsp1 alleles) affect the distribution of the red and brown screening pigments of the eyes. Most of the distally-located structural mutants show dosage compensation, wa/Y males having the same eye color as wa/wa females and do not suppress (but may interact with) zeste. Green (1959a) found that wi fails to show dosage compensation and does not suppress zeste; but wh exhibits both zeste suppression and dosage compensation. In spite of their heterogeneity, the alleles at the white locus fail to complement each other except for wsp1 which partially complements all other w alleles except in the presence of za (Babu and Bhat, 1980). Some white alleles (wc for example) are extremely unstable (Green, 1976); w1 is slightly unstable, giving rise to we and wh, mutants with darker eyes than w1. The locus is characterized by asymmetrical recombination involving transposons; the mutants wr,def and wr,dup are the result of such exchange (Davis, Shen and Judd, 1987). Some P-element white transformations show reproducible patterns of pigmentation which can be altered by the trans-acting gene zeste (Rubin, Hazelrigg, Karess, Laski, Laverty, Levis, Rio, Spencer and Zuker, 1985).

      Origin and Etymology
      Discoverer
      Etymology
      Identification
      External Crossreferences and Linkouts ( 76 )
      Sequence Crossreferences
      NCBI Gene - Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes, and links to genome-, phenotype-, and locus-specific resources worldwide.
      GenBank Protein - A collection of sequences from several sources, including translations from annotated coding regions in GenBank, RefSeq and TPA, as well as records from SwissProt, PIR, PRF, and PDB.
      RefSeq - A comprehensive, integrated, non-redundant, well-annotated set of reference sequences including genomic, transcript, and protein.
      UniProt/Swiss-Prot - Manually annotated and reviewed records of protein sequence and functional information
      Other crossreferences
      Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
      Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
      Flygut - An atlas of the Drosophila adult midgut
      GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
      iBeetle-Base - RNAi phenotypes in the red flour beetle (Tribolium castaneum)
      KEGG Genes - Molecular building blocks of life in the genomic space.
      modMine - A data warehouse for the modENCODE project
      Linkouts
      BioGRID - A database of protein and genetic interactions.
      DroID - A comprehensive database of gene and protein interactions.
      DRSC - Results frm RNAi screens
      FLIGHT - Cell culture data for RNAi and other high-throughput technologies
      FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
      FlyCyc Genes - Genes from a BioCyc PGDB for Dmel
      FlyMine - An integrated database for Drosophila genomics
      Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
      InterologFinder - Protein-protein interactions (PPI) from both known and predicted PPI data sets.
      MIST (genetic) - An integrated Molecular Interaction Database
      MIST (protein-protein) - An integrated Molecular Interaction Database
      Synonyms and Secondary IDs (17)
      Reported As
      Symbol Synonym
      BACN33B1.1
      e(g)
      m(g)