5kb deletion removing most of the transcription unit.
sqhAX3 mutant germline clones eventually stop producing egg chambers, but some egg chambers develop until stage 9 of oogenesis, and most of these exhibit polarity defects (i.e. mislocalized Staufen protein; mislocalized Par-1 protein).
sqhAX3 heterozygotes bearing two copies of sqhT20A produce oocytes with polarity defects (i.e. mislocalized Staufen protein).
sqhAX3 mutant clones of cells in the pupal retina have enlarged apical areas compared to controls.
sqhAX3 homozygous clonal neuroblasts in the larval brain fail to divide.
sqhAX3 heterozygotes do not show significant differences in wing size, as compared to controls.
The mitochondria in the neurons of heterozygous sqhAX3 adult brains are markedly elongated compared to controls.
Approximately 38% of sqhAX3/Y stage 16 embryos show laterality defects in the proventriculus and anterior midgut. The laterality of the other parts of the embryonic gut, including the hindgut and the posterior part of the midgut is normal in these mutants. The proventriculus and the anterior midgut do not rotate (as in wild-type) in these mutants at stages 15 to 17.
Homozygous stage 16 embryos have shorter dorsal trunks than normal, although they are contiguous.
Single cell clones of sqhAX3 exhibit an increased apical cell area. Adherens junctions in multiple cell clones are intact.
sqhAX3 mutant follicle cell clones are extremely flat and appear stretched. In many mutant egg chambers there are gaps in the follicular epithelium, suggesting that stretching of the follicle cells eventually disrupts the monolayer. These cells still retain polarity. The shape change found in the mutant follicle cell clones alters the morphology of the egg chamber, with the germ line cyst bulging out in regions covered by sqhAX3 mutant follicle cells.
sqhAX3 mutant follicle cell clones show a reduced number of phospho-His3-positive cells, huge nuclei, and abnormally large cells, indicating a defect in cytokinesis.
Mutant embryos exhibit defects in germ band elongation.
When a border cell is homozygous for sqhAX3 (part of a somatic clone), but is surrounded by wild-type border cells, it migrates with the cluster and sends out long cellular projections. However, such cells are often left behind by the migrating border cell cluster. Left behind mutant cells do not initiate migration on their own, and form abnormally long and convoluted cellular extensions.
Homozygous clones in the mushroom body result in proliferation defects in neuroblasts.
Most homozygotes die during the first larval instar stage. Homozygous germ line clones produce a few highly abnormal egg chambers, with 64% of the egg chambers having less than half the normal number of nurse cells, and 24% being comprised of just two large cells, apparently nurse cells, with large nuclei. 60% of the egg chambers contain at least one, and often several, binuclear or multinuclear nurse cells. The most advanced egg chambers attain the size and shape expected for stage 11-12, although the oocyte occupies an abnormally small volume in these egg chambers, and chorion deposition is seen around both the oocyte and nurse cells. Most ring canals are deformed. The oocyte is at the anterior of the egg chamber in 5% of cases. No eggs are laid.
Lethal either as a late embryo or early larva, with variable dorsal closure defects, depending on the maternal dose.
sqhAX3 has abnormal axis specification | embryonic stage 17 | male limited phenotype, enhanceable by zip3
sqhAX3 has abnormal axis specification | embryonic stage 16 | male limited phenotype, enhanceable by zip3
sqhAX3 has abnormal axis specification | embryonic stage 15 | male limited phenotype, enhanceable by zip3
sqhAX3 has abnormal cell shape | somatic clone phenotype, suppressible by ovoD1
sqhAX3 has abnormal cytokinesis | somatic clone phenotype, suppressible by ovoD1
sqhAX3/sqh[+] is an enhancer of visible phenotype of Scer\GAL4hs.PB, towUAS.cCa
sqhAX3/sqh[+] is a suppressor | partially of decreased size | adult stage phenotype of Scer\GAL4A9, ShrmA.UAS
sqhAX3/sqh[+] is a suppressor | partially of visible | adult stage phenotype of Scer\GAL4A9, ShrmA.UAS
sqhAX3/sqh[+] is a suppressor | partially of abnormal size | adult stage phenotype of Scer\GAL4nub-AC-62, ykiUAS.Tag:FLAG,Tag:Myr(Src64B)
sqhAX3/sqh[+] is a suppressor | partially of visible | adult stage phenotype of Scer\GAL4nub-AC-62, ykiUAS.Tag:FLAG,Tag:Myr(Src64B)
sqhAX3 is a suppressor of abnormal cell shape | extended germ band stage phenotype of upd1YM55
sqhAX3/sqh[+] is a suppressor of abnormal neuroanatomy phenotype of RhoGAPp190RNAi.GAP.UAS, Scer\GAL4ey-OK107
sqhAX3/sqh[+] is a non-suppressor of abnormal size | adult stage phenotype of Scer\GAL4nub-AC-62, ykiUAS.cXa.Tag:FLAG
sqhAX3 has embryonic/larval anterior midgut | embryonic stage 16 | male limited phenotype, enhanceable by zip3
sqhAX3 has embryonic/larval anterior midgut | embryonic stage 15 | male limited phenotype, enhanceable by zip3
sqhAX3 has embryonic/larval anterior midgut | embryonic stage 17 | male limited phenotype, enhanceable by zip3
sqhAX3 has embryonic proventriculus | embryonic stage 16 | male limited phenotype, enhanceable by zip3
sqhAX3 has embryonic proventriculus | embryonic stage 15 | male limited phenotype, enhanceable by zip3
sqhAX3 has embryonic proventriculus | embryonic stage 17 | male limited phenotype, enhanceable by zip3
sqhAX3 has epithelium | somatic clone phenotype, suppressible by ovoD1
sqhAX3 has follicle cell | somatic clone phenotype, suppressible by ovoD1
sqhAX3 has egg chamber | somatic clone phenotype, suppressible by ovoD1
sqhAX3/sqh[+] is an enhancer of adult brain phenotype of Hsap\MAPTR406W.UAS, Scer\GAL4elav.PU
sqhAX3/sqh[+] is an enhancer of mitochondrion phenotype of Hsap\MAPTR406W.UAS, Scer\GAL4elav.PU
sqhAX3/sqh[+] is an enhancer of wing hair | increased number phenotype of Scer\GAL4hs.PB, towUAS.cCa
sqhAX3/sqh[+] is a suppressor | partially of wing phenotype of Scer\GAL4A9, ShrmA.UAS
sqhAX3/sqh[+] is a suppressor | partially of wing phenotype of Scer\GAL4nub-AC-62, ykiUAS.Tag:FLAG,Tag:Myr(Src64B)
sqhAX3 is a suppressor of ectoderm | extended germ band stage phenotype of upd1YM55
sqhAX3/sqh[+] is a suppressor of mushroom body vertical lobe phenotype of RhoGAPp190RNAi.GAP.UAS, Scer\GAL4ey-OK107
sqhAX3/sqh[+] is a suppressor of wing hair | increased number phenotype of fzI.hs
sqhAX3/sqh[+] is a non-suppressor of wing phenotype of Scer\GAL4nub-AC-62, ykiUAS.cXa.Tag:FLAG
The multiple wing hair phenotype caused by expression of towScer\UAS.cCa under the control of Scer\GAL4hs.PB using heat shock at 24 hours after puparium formation is enhanced if the flies are also carrying one copy of sqhAX3.
One copy of sqhAX3 enhances the increase in mitochondria length seen when Hsap\MAPTR406W.Scer\UAS is expressed under the control of Scer\GAL4elav.PU.
sqhAX3 embryos which carry sqhRLC.T:Avic\GFP-S65T and which also express slmbScer\UAS.T:Zzzz\vhhGFP4 under the control of Scer\GAL4332.3 in the postmitotic amnioserosa cells show a dorsal open phenotype.
sqhAX3 is partially rescued by sqhE20.E21
sqhAX3 is partially rescued by sqhE21.Tag:FLAG
sqhAX3 is partially rescued by sqhA21.Tag:FLAG
sqhAX3 is not rescued by sqhA20.A21.Tag:FLAG
Expression of sqhRLC.T:Avic\GFP-S65T rescues the loss of rotation in the proventriculus and anterior midgut seen in sqhAX3/Y.
Expressing one copy of the sqhE20.E21 transgene substantially restores both oogenesis and subsequent axial expansion in sqhAX3 germline clones.
Homozygous lethality is fully rescued by sqhA20.T:Zzzz\FLAG, partially rescued by sqhE21.T:Zzzz\FLAG (sqhAX3 animals carrying sqhE21.T:Zzzz\FLAG survive to the late pupal stage) and by sqhA21.T:Zzzz\FLAG (sqhAX3 animals carrying sqhA21.T:Zzzz\FLAG survive to the early pupal stage), and not rescued by sqhA20.A21.T:Zzzz\FLAG (sqhAX3 animals carrying sqhA20.A21.T:Zzzz\FLAG die as first instar larvae). Homozygous female germline clones expressing sqhA20.A21.T:Zzzz\FLAG have phenotypes nearly indistinguishable from homozygous female germline clones that do not carry sqhA20.A21.T:Zzzz\FLAG. The morphology of egg chambers derived from homozygous female germline clones expressing sqhA21.T:Zzzz\FLAG is grossly normal, with a well-differentiated oocyte and accompanying nurse cells. However, 73% of egg chambers contain at least one binuclear cell, and 80% contain less than 15 nurse cells. Substantial nurse cell cytoplasm remains untransferred even by stage 13 in many egg chambers. These clones produce some eggs. Approximately 23% of eggs laid by females carrying homozygous germline clones expressing sqhA21.T:Zzzz\FLAG and fertilised by males homozygous for a sqh+ transgene begin development, but they do not hatch. Nuclear migration in these eggs is often isotropic, producing a spherical cloud of nuclei. Approximately 80% of egg chambers derived from homozygous female germline clones expressing sqhE21.T:Zzzz\FLAG appear wild-type. 15% contain fewer than 15 nurse cells, and only 9% contain any binuclear cells. Stage 13 egg chambers containing significant amounts of nurse cell cytoplasm are relatively common, although 80% of eggs are wild-type in length. Approximately 60% of eggs laid by females carrying homozygous germline clones expressing sqhE21.T:Zzzz\FLAG and fertilised by males homozygous for a sqh+ transgene begin development, and 41% of these embryos hatch. 46% of these larvae reach adulthood.