Endocycles support tissue growth and regeneration of the adult Drosophila accessory gland

Abstract

AbstractThe Drosophila melanogaster accessory gland is a functional analog of the mammalian prostate made up of two secretory epithelial cell types, termed main and secondary cells. This tissue is responsible for making and secreting seminal fluid proteins and other molecules that contribute to successful reproduction. Here we show that similar to the mammalian prostate, this tissue grows with age. We find that the adult accessory gland grows in part via endocycles to increase DNA content and cell size, independent of mating status. The differentiated, bi-nucleated main cells remain poised to endocycle in the adult gland and upregulation of signals that promote endocycling and tissue growth are sufficient to trigger dramatic endocycling leading to increases in cell size and ploidy. The main cells of this tissue remain poised to enter the cell cycle and endocycling of main cells increases during recovery from severe tissue damage. Our data establish that the adult accessory gland is not quiescent, but instead uses endocycles to maintain the accessory gland’s critical function throughout the fruit fly’s lifespan.