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General Information
Symbol
Dmel\mei-W681
Species
D. melanogaster
Name
FlyBase ID
FBal0012191
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Allele class
Mutagen
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

Insertion of approximately 5kb into the second exon.

Insertion components
?{}mei-W681
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 ( 0 )
Disease
Interaction
References
Comments on Models/Modifiers Based on Experimental Evidence ( 0 )
 
Phenotypic Data
Phenotypic Class
Phenotype Manifest In
Detailed Description
Statement
Reference

Homozygous females show elevated levels of chromosome nondisjunction of the X chromosome (34.7%).

X chromosome nondisjunction is increased to 51.9% in homozygous XXY females, with 95% of the events involving the two X chromosomes segregating from the Y.

The majority of mei-W681/mei-W68k05603 eggs (94%) show a wild-type number of dorsal appendages.

mei-W68L1/mei-W681 or mei-W681/mei-W681 female meioses exhibit crossover frequency reduction along chromosome 2, as compared to wild type.

Crossing over is reduced in mei-W68L1/mei-W681 females. Homozygotes lack meiotic crossing over. Premeiotic exchanges occur in homozygous females. mei-W681 is recessive to wild type when nondisjunction frequencies are examined but has dominant effects on crossing over. Homozygous and mei-W68L1/mei-W681 females show normal dynamics of germ-line mitotic divisions. The dynamics of entry into meiosis or exit of the losing pro-oocyte is also normal. The synaptonemal complex appears to be of normal morphology in homozygous females and appears to be between homologs. There are no late recombination nodules and early recombination nodules also appear to be missing. A novel structure ("noodle"), that resembles recombination nodules (RNs) in being adjacent to the central region of the synaptonemal complex, is seen. Noodles are smaller than RNs and are also less dense. The number of noodles increases at least up to the time cytoplasmic flow begins and they persist post-cytoplasmic flow.

Severe mutation.

Ultrastructural studies of pachytene reveal synaptonemal complex that is normal in structure and length and which undergoes the same changes in length as is observed in wild type as the cells progress through pachytene; chromocentral organization and chromatin condensation are also normal. However, no late recombination nodules were observed in the nine nuclei reconstructed which were between the developmental landmarks which demark their presence in wild type.

Metaphase arrest prevented.

Females homozygous for mei-W68 show a complete absence of meiotic recombination (Baker, unpublished data). A less severe allele (mei-W68L1-Lindsley) reduces exchange to approximately 60% of control levels and also alters the distribution of residual exchanges. Analysis of mitotic chromosome behavior (Baker et al., 1978) suggests that the mei-W68+ gene product is also required in mitotic cells.

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

mei-W681 is a suppressor | partially of female sterile phenotype of spn-BBU

mei-W681 is a suppressor of female sterile | recessive phenotype of spn-BBU

Other
Phenotype Manifest In
Suppressor of
Statement
Reference

mei-W681 is a suppressor of nurse cell phenotype of okrAA/okrRU, p53unspecified

mei-W681/mei-W681 is a suppressor of chorion phenotype of okrAA/okrRU

mei-W681/mei-W681 is a suppressor | partially of oocyte phenotype of mio2

mei-W68[+]/mei-W681 is a suppressor | partially of nurse cell phenotype of mio2/mio1

mei-W68[+]/mei-W681 is a suppressor | partially of oocyte phenotype of mio2/mio1

mei-W681 is a suppressor | partially of egg chamber phenotype of mio2

mei-W68[+]/mei-W681 is a suppressor | partially of nurse cell phenotype of mio2

mei-W68[+]/mei-W681 is a suppressor | partially of oocyte phenotype of mio2

mei-W681/mei-W681 is a suppressor | partially of nurse cell phenotype of mio2

NOT Suppressor of
Statement
Reference

mei-W681 is a non-suppressor of karyosome phenotype of Src64BΔ17

Other
Statement
Reference

Df(2R)LL5, mei-41D3, mei-W681 has oocyte nucleus & meiotic cell cycle phenotype

Additional Comments
Genetic Interactions
Statement
Reference

The ventralised eggshell phenotype seen in eggs derived from homozygous CycGHR7 females is suppressed in more than 90% of eggs if the females are also carrying mei-W681/mei-W68k05603.

Single-gene mutants show 15 nurse cell nuclei per egg chamber, but p53unspecified, okrAA/okrRU ovaries exhibit a broad distribution, ranging from 9 to 40 nuclei per egg chamber, which is restored to normal in mei-W681, okrAA/okrRU, p53unspecified animals.

While p53unspecified, okrAA/okrRU double mutants are sterile, fertility is restored in mei-W681, okrAA/okrRU, p53unspecified triple mutant females.

mei-W681 ; yemα1/Df(3R)3450 oocytes undergo precocious anaphase I (as occurs in mei-W681 single mutants), but meiosis II spindles are rarely observed in the double mutants (in contrast to mei-W681 single mutants where a greater proportion of the oocytes reach meiosis II).

The fused dorsal appendage phenotype of armi72.1/armi1 eggs is not suppressed in mei-W681/mei-W68k05603; armi72.1/armi1 eggs.

Transformation of oocytes to nurse cells in mio2 homozygous females is partially suppressed by mei-W681/+ or mei-W681/mei-W681. The block in oogenesis at around stage 5 seen in mio2 homozygous females is also partially suppressed by mei-W681, producing egg chambers that often undergo vitellogenesis and develop to the late stages of oogenesis. Transformation of oocytes to nurse cells in mio2/mio1 females is suppressed by mei-W681/+.

Has no effect on the frequency of X-Y chromosome nondisjunction seen in Df(1)X-1-53B males.

In mei-41D3; mei-W681/Df(2R)LL5 oocyte nuclei most nuclei are either exhibit disorganised spindles and multiple chromatin masses or premature anaphases.

In mei-41D3; mei-W681/Df(2R)LL5 oocytes most nuclei exhibit either disorganised spindles and multiple chromatin masses or premature anaphases.

Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Fails to complement
Comments
Images (0)
Mutant
Wild-type
Stocks (2)
Notes on Origin
Discoverer
Comments
Comments

No gene conversion or intragenic crossovers are observed in an assay of intragenic recombination at ry. The frequency of crossing-over on the entire X and second chromosome is much reduced: isolated recombination events suggest that the recombination taken place is in fact a mitotic and not a meiotic event. Examination of oocytes to study meiotic recombination events in sister chromatids reveals there are no cross over events. Double stranded breaks are not left unrepaired. Synaptonemal complex formation is not disrupted, meiotic progression is normal.

External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (3)
References (26)