Rab11 negatively regulates wingless preventing JNK-mediated apoptosis in Drosophila epithelium during embryonic dorsal closure

AbstractRab11, a small Ras like GTPase marking the recycling endosomes, plays instrumental roles inDrosophila embryonic epithelial morphogenesis where an array of reports testify its importance in the maintenance of cyto-architectural as well as functional attributes of the concerned cells. Proper Rab11 functions ensure a precise regulation of developmentally active cell signaling pathways which in turn promote the expression of morphogens and other physico-chemical cues which finally forge an embryo out of a single layer of cells. Earlier reports have established thatRab11 functions are vital for fly embryonic development where amorphic mutants such asEP3017 homozygotes show a fair degree of epithelial defects along with incomplete dorsal closure. Here, we present a detailed account of the effects ofRab11 loss of function in the dorso-lateral epithelium which resulted in severe dorsal closure defects along with an elevated JNK-Dpp expression. We further observed that the dorso-lateral epithelial cells undergo epithelial to mesenchymal transition as well as apoptosis inRab11 mutants with elevated expression levels of MMP1 and Caspase-3, where Caspase-3 contributes to theRab11 knockout phenotype contrary to the knockdown mutants or hypomorphs. Interestingly, the elevated expressions of the core JNK-Dpp signaling could be rescued with a simultaneous knockdown ofwingless in theRab11 knockout mutants suggesting a genetic interaction ofRab11 with the Wingless pathway during dorsal...

Source: Cell and Tissue Research - January 27, 2023 Category: Cytology Source Type: research