The mutation results in a truncated protein only encoding part of the kinase domain.
Amino acid replacement: K348term.
A12513243T
K348term | sti-PA; K352term | sti-PB
K348term
Site of nucleotide substitution in mutant inferred by FlyBase based on reported amino acid change.
abnormal size | larval stage (with sti1)
lethal | heat sensitive (with stiZ3-5829)
visible | heat sensitive (with stiZ3-5829)
eye | heat sensitive (with stiZ3-5829)
imaginal disc (with sti1)
imaginal disc (with sti2)
imaginal disc (with sti4)
nucleus & follicle cell | conditional - heat sensitive (with stiZ3-5829)
The fraction of stiZ3-5829/sti3 individuals recovered in a cross between stiZ3-5829/TM6B and sti3/TM6B animals is significantly less than expected at 25[o]C, whereas at 18[o]C, there is no significant difference between the fraction of heterozygous and stiZ3-5829/sti3 progeny recovered. At 18[o]C, both male and female stiZ3-5829/sti3 progeny are equally represented, whereas at 25[o]C, male stiZ3-5829/sti3 progeny are significantly reduced.
The nuclear diameter of stage 12-13 stiZ3-5829/sti3 follicle cells is normal at 18[o], but is increased compared to wild type at 21[o]C.
In stiZ3-5829/sti3 flies, 100% have missing eye bristles and 37% have rough eyes when reared at 21[o]C. At 25[o]C, 100% of stiZ3-5829/sti3 adults have missing eye bristles and rough eyes.
The rough eye phenotype of stidsRNA.Sym.Scer\UAS expression under the regulation of Scer\GAL4ey.PB is enhanced by the presence of sti3. sti1/sti3, sti2/sti3, and sti4/sti3 flies have very small imaginal discs and are lethal at the prepupal stage.
In trans to a deficiency, mitotic chromosomes (both sisters and heterologues) stuck together and show metaphase delay; "successful" anaphase fragments the chromosomes.
sti3/sti[+] is a suppressor of visible phenotype of AGO1UAS.cZa, Scer\GAL4GMR.PF
sti3/sti[+] is a suppressor of eye phenotype of AGO1UAS.cZa, Scer\GAL4GMR.PF
The rough and small eye phenotypes of flies expressing AGO1Scer\UAS.cZa under the control of Scer\GAL4GMR.PF are suppressed by sti3/+, with suppression consistently being stronger in females than in males.
The sti3 mutation does not modify the RacGAP50CdsRNA.Scer\UAS (under the regulation of Scer\GAL4ey.PB) rough eye phenotype.
Carpenter.
Based on lethal phase analysis the following sti alleles can be ranked from the most severe to the weakest as follows: sti3 > sti1 = sti2 = sti4 > sti5.