Mating induces switch from hormone-dependent to hormone-independent steroid receptor –mediated growth in < i > Drosophila < /i > secondary cells

by Aaron Leiblich, Josephine E. E. U. Hellberg, Aashika Sekar, Carina Gandy, Claudia C. Mendes, Siamak Redhai, John Mason, Mark Wainwright, Pauline Marie, Deborah C. I. Goberdhan, Freddie C. Hamdy, Clive Wilson Male reproductive glands like the mammalian prostate and the pairedDrosophila melanogaster accessory glands secrete seminal fluid components that enhance fecundity. In humans, the prostate, stimulated by environmentally regulated endocrine and local androgens, grows throughout adult life. We previously showed that in fly accessory glands, secondary cells (SCs) and their nuclei also grow in adults, a process enhanced by mating and controlled by bone morphogenetic protein (BMP) signalling. Here, we demonstrate that BMP-mediated SC growth is dependent on the receptor for the developmental steroid ecdysone, whose concentration is reported to reflect sociosexual experience in adults. BMP signalling appears to regulate ecdysone receptor (EcR) levels via one or more mechanisms involving the EcR ’s N terminus or the RNA sequence that encodes it. Nuclear growth in virgin males is dependent on ecdysone, some of which is synthesised in SCs. However, mating induces additional BMP-mediated nuclear growth via a cell type–specific form of hormone-independent EcR signalling, which drives genome endoreplication in a subset of adult SCs. Switching to hormone-independent endoreplication after mating allows growth and secretion to be hyperactivated independently of ecdysone levels in...
Source: PLoS Biology: Archived Table of Contents - Category: Biology Authors: Source Type: research