Amino acid replacement: R343term.
C4063506T
R343term | dib-PA
R343term
Site of nucleotide substitution in mutant inferred by FlyBase based on reported amino acid change.
embryo | dorsal closure stage (with dibF8)
embryo | embryonic stage 14 (with dibF8)
yolk granule (with dibF8)
dibP3/dibF8 embryos have no denticle belts, dorsal hairs or differentiated mouth parts. Only a thin cuticular remnant containing both dorsal and anterior holes is secreted by most embryos. dibP3/dibF8 embryos appear to develop normally to approximately stage 14. At this point, many morphogenetic movements including dorsal closure, head involution, midgut morphogenesis and hindgut looping become abnormal. Midgut cells form the bilateral vessel but often fail to migrate to enclose the gut and the normal constrictions are either not formed or form abnormally. The failure of the midgut to enclose the yolk leads to yolk granules being distributed throughout the embryo, and they often extrude through the dorsal opening. During this time, the epidermis begins to contract along the anteroposterior axis leaving the thoracic and abdominal segments in a highly compacted state (possibly because head segments fail to involute properly). The hindgut becomes more extended than normal or may show unusual coiling. Many embryos never complete dorsal closure and when development terminates, the embryos are highly contracted with non-involuted head segments protruding anteriorly and gut and yolk protruding posteriorly. The amount of cell death appears to be normal during these abnormal late stages of embryogenesis. dibP3/dibF8 embryos derived from females with homozygous dibF8 germline clones (lacking both maternal and zygotic dib function) show the same range and timing of defects as dibP3/dibF8 embryos (lacking zygotic dib function), suggesting that dib is not required in the germline during oogenesis or during early embryogenesis before stage 14. A low level (less than 1%) of escapers is seen in dibP3/dib13A animals. These flies appear normal and are fertile.
dibP3/dibF8 is rescued by Scer\GAL42-286/dibUAS.cOa
dibP3/dibF8 is rescued by Scer\GAL4P0206/dibUAS.cOa
Expression of dibScer\UAS.cOa under the control of either Scer\GAL42-286 or Scer\GAL4P0206 rescues the lethality of dibP3/dibF8 animals and results in fertile males.