- Tools
- Downloads
- Links
- Community
- About
- Help
FB2026_01
,
released March 12, 2026
actin filament & egg chamber
98% of eggs laid by heterozygous females have short and broad double or single dorsal appendages.
Approximately 67% of stage 10B-12 egg chambers of heterozygous females have insufficient actin bundling in the nurse cells. The filaments that do form around the nurse cell nuclei appear shorter and less abundant than normal.
Homozygous border cell clones show normal migration.
Mutant egg chambers often contain collapsed ring canals and completely lack actin bundles.
Nurse cells lack actin halo, transport of cytoplasm is blocked.
Egg chambers appear normal until early stage 10, but after stage 10 the nurse cells fail to regress and deliver their contents into the oocyte. Consequently the oocytes are approximately half the normal size. The cytoplasmic actin bundles that assemble in wild type nurse cells just prior to the onset of rapid transport are missing. The nurse cell nuclei assume an elongated morphology and often extend through the ring canals. The few eggs laid by these females fail to develop.
Eggs are tiny due to a failure to transport nurse cell content into the oocyte.
Posterior localization of vas protein.
Oogenesis is abnormal in qua1 females; the nurse cell contents are not deposited into the oocyte, resulting in very small cup-like eggs.
female-sterile nurse-cell contents not transported into the egg; follicle cells produce normal chorion around tiny eggs, which remain unfertilized.
qua1 has nurse cell ring canal phenotype, non-enhanceable by ActnΔ233/ActnΔ208
qua1 has dorsal appendage phenotype, suppressible by spoon1/spoon[+]
qua1 has dorsal appendage phenotype, suppressible by Df(1)1/+
qua1 has dorsal appendage phenotype, non-suppressible by Df(1)2/+
qua1 has nurse cell ring canal phenotype, non-suppressible by ActnΔ233/ActnΔ208
Only 39.2% of eggs laid by qua1/+ spoon1/+ double heterozygous females have short and broad double or single dorsal appendages.
Only 39.2% of eggs laid by qua1/+ Df(1)1/+ double heterozygous females have short and broad double or single dorsal appendages.
The reduced actin bundling seen in the nurse cells of stage 10B-12 egg chambers of qua1/+ females is suppressed by spoon1/+, with less than 20% of the double mutant egg chambers showing an actin polymerisation defect.
Wieschaus and Nusslein-Volhard.