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General Information
Symbol
Dmel\piwi1
Species
D. melanogaster
Name
FlyBase ID
FBal0024637
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Also Known As
piwi1
Key Links
Allele class
Nature of the Allele
Allele class
Mutations Mapped to the Genome
 
Type
Location
Additional Notes
References
Associated Sequence Data
DNA sequence
Protein sequence
 
 
Progenitor genotype
Cytology
Nature of the lesion
Statement
Reference

P{PZ} is inserted in first exon. The orientation of the P{PZ} is opposite to that of the gene.

Insertion components
P{PZ}piwi1
Product class / Tool use(s)
Encoded product / tool
Expression Data
Reporter Expression
Additional Information
Statement
Reference
 
Marker for
Reflects expression of
Reporter construct used in assay
Human Disease Associations
Disease Ontology (DO) Annotations
Models Based on Experimental Evidence ( 0 )
Disease
Evidence
References
Modifiers Based on Experimental Evidence ( 1 )
Disease
Interaction
References
ameliorates  brain cancer
Comments on Models/Modifiers Based on Experimental Evidence ( 0 )
 
Disease-implicated variant(s)
 
Phenotypic Data
Phenotypic Class
Phenotype Manifest In
Detailed Description
Statement
Reference

piwi1/piwi2 mutants show defects in the ovaries.

piwi1/piwi2 ovaries show abnormal cell death.

Only 2% of embryos from piwi1 germline clones are able to produce cuticle. Of those with cuticle 22/23 have head skeleton defects.

Projection neuron morphogenesis is normal in mutant animals.

piwi1 flies show a disruption of the heterochromatic silencing of the P{T1} reporter in line P{T1}T190-177 and of the P{T1(-FRT)} reporter in line P{T1(-FRT)}T190-177.

Embryos produced by females with piwi1 germline clones contain on average 7.5 pole cells at mitotic cycle 14, as compared to 24 pole cells in wild-type embryos at the same stage. 33% of the embryos from the piwi1 clones have no pole cells at all.

Ovarioles in mutant females typically contain a germlineless germarium and two to three egg chambers.

Suppressor of repeat-induced silencing, as seen at heterochromatic tandem arrays of insertions of the P{lacW} transposon.

Homozygous females do not lay eggs. The small number of eggs that they do produce are retained in the ovary and eventually atrophy. Homozygous germline stem cells (GSCs) (induced by mitotic recombination immediately prior to oogenesis) are present three weeks following oogenesis. The homozygous GSCs divide four-fold slower than their wild-type counterparts. Cysts and postgerminal egg chambers derived from these homozygous GSCs usually develop normally. piwiEP1024/piwi1 ovaries and testes show a typical piwi1 mutant phenotype.

Female germ-line stem cells are of normal number but are mispositioned in third instar ovaries. Number of ovariole in most adult ovaries is within the normal range. Germ line stem cells differentiate without self-renewing divisions immediately following the initiation of oogenesis. Germ line stem cells and cystoblasts are undetectable in mutant ovaries, as indicated by the absence of spectrosome-containing germ cells. Most ovaries contain differentiated germ-line cysts whose number approximately equals that of the germ line stem cells. Cysts are much larger in size and contain two- to multicell stage fusomes, indicating their differentiated state. Adult ovaries contain only 2 normal or abnormal egg chambers connected to a germarium lacking other germ line cells. Embryos derived from germ-line clones are arrested in embryogenesis, and cannot be rescued by paternal piwi+. They have various defects, including mitotic defects during cleavage stage or later severe deformation of head region. Somatic clonal analysis reveals that piwi function is not required in follicle cells for egg chamber development.

Mutant males show severe defects in spermatogenesis. Mutant testes only contain 1-6 bundles of mature sperm but no other germline cells. Ovarioles are almost completely devoid of germline cells. Individual ovarioles are present but difficult to recognise. At low frequency some ovarioles contain a few developing egg chambers or mature eggs.

male-sterile female-sterile ovaries rudimentary, degenerate

External Data
Interactions
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Enhancer of
Statement
Reference

piwi[+]/piwi1 is an enhancer of visible phenotype of KrIf-1

Suppressor of
Statement
Reference
NOT Suppressor of
Statement
Reference

piwi1 is a non-suppressor of neoplasia phenotype of bratk06028

Phenotype Manifest In
NOT Enhanced by
Statement
Reference

piwi1 has germline stem cell phenotype, non-enhanceable by fs(1)Yb1

Suppressed by
Statement
Reference
NOT suppressed by
Statement
Reference

piwi1 has germline stem cell phenotype, non-suppressible by fs(1)Yb1

Enhancer of
Statement
Reference

piwi[+]/piwi1 is an enhancer of eye phenotype of KrIf-1

NOT Enhancer of
Statement
Reference

piwi1 is a non-enhancer of germline stem cell phenotype of fs(1)Yb1

Suppressor of
Statement
Reference

piwi[+]/piwi1 is a suppressor | partially of testis phenotype of Tudor-SN0614/Tudor-SN1120

piwi1 is a suppressor of eye phenotype of E2f1dsRNA.C.UAS, Scer\GAL4I-76-D

piwi1 is a suppressor of antenna phenotype of E2f1dsRNA.C.UAS, Scer\GAL4I-76-D

piwi1 is a suppressor of wing phenotype of sdFab-X

NOT Suppressor of
Statement
Reference

piwi1/piwi1 is a non-suppressor of eye phenotype of wdsRNA.GMR/wdsRNA.GMR

piwi1 is a non-suppressor of germline stem cell phenotype of fs(1)Yb1

Additional Comments
Genetic Interactions
Statement
Reference

piwi1/+ (or even more so, piwi1/piwi2) significantly partially suppresses the swollen apical tip of the testis phenotype seen in Tudor-SN0614/Tudor-SN1120 males. piwi1/piwi2 suppresses infertility seen in Tudor-SN0614/Tudor-SN1120 males. Tudor-SN0614/Tudor-SN1120 partially suppresses ovary defects in piwi1/piwi2 females.

piwi1/+ enhances the eye outgrowth phenotype phenotype of KrIf-1; approximately 7% of the progeny have an eye outgrowth phenotype in a cross of piwi1/+ females to KrIf-1/+ males. However, the reciprocal cross of KrIf-1/+ females to piwi1/+ males does not result in progeny with an eye outgrowth phenotype, indicating a maternal effect.

The frequency with which l(3)mbtts1 larval brain tissue develops into tumours after allograft into adult host flies (taking over the entire abdomen of the host) is markedly reduced if the transplanted tissue is also homozygous for piwi1.

The frequency with which bratk06028 larval brain tissue develops into tumours after allograft into adult host flies (taking over the entire abdomen of the host) is not significantly altered if the transplanted tissue is also homozygous for piwi1.

piwi1 suppresses the eye and antenna traits of flies expressing E2fdsRNA.C.Scer\UAS under the control of Scer\GAL4I-76-D.

The yellowish eye colour caused by expression of one copy of wdsRNA.GMR in a wild-type background is not altered if the flies are also homozygous for piwi1.

piwi1/+ does not impair cytotype-mediated repression of P-element excision.

The wing phenotype of sdFab-X flies is suppressed in sdFab-X;piwi1 flies.

piwi1 ; bamΔ86 double mutant ovarioles have mildly tumorous germaria filled with 50-300 undifferentiated germ cells with no apparent egg chamber development.

Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Not rescued by
Comments

Expression of two copies of piwiDUO.T:Hsap\MYC rescues the ovary phenotypes and egg laying defects seen in homozygous piwi1 mutant flies.

Expression of two copies of piwi5'T:Hsap\MYC rescues the ovary phenotypes and egg laying defects seen in homozygous piwi1 mutant flies.

When piwiEP1024 is overexpressed under the control of Scer\GAL4hs.PB using heat shock treatment (1 hour at 37oC every day starting from the larval stage) in a piwiEP1024/piwi1 background, significant rescue of the piwiEP1024/piwi1 mutant phenotype is seen in both females and males. Specifically, in females, germline stem cells are maintained and a string of developing egg chambers are observed, while in males, germline stem cells are also rescued and spermatogenesis is fully restored. Fertility is rescued to wild-type levels. Heat shock starting at the pupal stage does not rescue fertility.

Embryos derived from germ-line clones are arrested in embryogenesis, and cannot be rescued by paternal piwi+.

Images (0)
Mutant
Wild-type
Stocks (1)
Notes on Origin
Discoverer
Comments
Comments

Mobilisation of the P{PZ} insertion reverts the mutant phenotype.

External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (3)
References (42)