No evidence of a deletion for, or break, in fog.
During stage 11 of embryogenesis, the salivary gland primordium of fkh6 homozygotes still forms an invagination pit, although frequently exhibiting a slight increase in width, still forms an apparently normal supra-cellular myosin cable, does not exhibit significant changes in circularity, and its cells still constrict apically, but frequently exhibits an abnormal ingression furrow along the edge, as compared to controls; the region to the anterior of the presumptive invagination site, however, fails to cluster the primordium cells with lower apical surface area, and these cells also only form small apical foci of myosin and Rok protein, as compared to controls. During later of oogenesis, this fogRA67-mutant primordium frequently exhibits internalization and migration defects, including being partially or completely externalized, as compared to controls.
fogRA67 is not rescued by Scer\GAL4fkh.PH/fogUAS.cDa
fogRA67 homozygous embryos exhibit defects in salivary gland primordium internalization, which are not rescued by the expression of fogScer\UAS.cDa under the control of Scer\GAL4fkh.PH.
This allele was originally thought to be Df(1)RA67, but complementation and molecular analysis failed to reveal any evidence of a deletion.