otuPΔ2 and otuPΔ5 are identical at the molecular level: otu sequences originating at the site of the parental P element insertion and extending to +673bp (in the second exon, just downstream of the translation start site) from the start of transcription are excised. However a second in-frame translation start codon is found one codon later, so the possible product differs from wild type only in the first two amino acids. The possibility of base substitutions in other parts of the protein has not been ruled out.
otuPΔ2 and otuPΔ5 have identical sequences. 16bp of the upstream P insert inverted repeat remains, followed by a 13bp stretch of unknown origin. The downstream end point of the deletion is at +674 in the otu gene, thus the major transcriptional start site and the entire transcribed leader region, including the translational start codon is gone. Upstream regulatory sequences and the minor transcriptional start sites are intact, and an alternative in-frame translational start codon (the third codon of the wild-type gene) is present.
673 bp deletion associated with the imprecise excision of P{}otu20.
Hypomorphic otuPΔ5 egg chambers typically reach stages 8-9, and occasionally stage 10.
Cytoplasmic dumping is blocked in homozygous egg chambers. The cytoplasmic actin cytoskeleton of nurse cells shows major disruptions, while the cortical actin appears normal.
When XY flies are transformed into pseudofemales by traHsp83.PS, otu activity is sufficient to allow XY germ cell proliferation. Frequency of agametic ovaries is higher than that of otu+/Y pseudofemales.
Large ovaries containing primarily late stage egg cysts characterized by pseudonurse cells and yolky oocytes.
DIF class allele.
DIF class phenotype.