TGF-β and BMP signals regulate insect diapause through Smad1-POU-TFAM pathway

In this study, we find that TGF-β superfamily signaling regulates Helicoverpa armigera diapause via a novel mechanism. Both TGF-β and BMP signals are weaker in the brains of diapause-destined pupae than in nondiapause-destined pupae, and the levels of p-Smad1, POU, TFAM, and mitochondrial activity are decreased in diapause pupae. Development in nondiapause pupae is delayed by an injection of TGF-β or BMP receptor inhibitors. Both TGF-β and BMP signals can activate a common target, Smad1. ChIP and EMSA assays indicate that Smad1 can bind to the POU promoter to regulate its expression. POU can improve the transcription of TFAM, which regulates mitochondrial activity. This is the first report showing that both TGF-β and BMP signals regulate development or diapause through the Smad1-POU-TFAM-mitochondrial activity in insects.Graphical abstract

Source: Biochimica et Biophysica Acta (BBA) Molecular Cell Research - July 11, 2018 Category: Molecular Biology Source Type: research