Drosophila jumu modulates apoptosis via a JNK-dependent pathway and is required for other processes in wing development

AbstractPrevious studies in several model organisms have revealed that members of the Forkhead (Fkh) transcription factor family have multiple functions.Drosophila Jumeau (Jumu), a member of this family, participates in cardiogenesis, hematopoiesis and immune system homeostasis. Here, we show that loss ofjumu function positively regulates or triggers apoptosis via a JNK-dependent pathway in wing development.jumu mutants showed reduced wing size and increased apoptosis. Moreover, we observed a loss of the anterior cross vein (ACV) phenotype that was similar to that observed in wings in which JNK signaling has been ectopically activated. The JNK signaling markerspuckered (puc) and p-JNK were also significantly increased in the wing discs ofjumu mutants. In addition, apoptosis induced by the loss ofjumu was rescued by knocking down JNK, indicating a role for JNK in reducingjumu-induced apoptosis. Jumu could also control wing margin development via the positive regulation ofcut expression, and the observed wing margin defect did not result from a loss ofjumu-induced apoptosis. Further,jumu deficiency in the pupal wing could induce multiple wing hairs via a Rho1-mediated planar cell polarity pathway, but abnormalRho1 expression was not whyjumu loss induced apoptosis via a JNK-dependent pathway in wing discs.
Source: Apoptosis - Category: Molecular Biology Source Type: research