Systemic and local effect of the < i > Drosophila headcase < /i > gene and its role in stress protection of Adult Progenitor Cells

by Panagiotis Giannios, Jordi Casanova During the development of a holometabolous insect such asDrosophila, specific group of cells in the larva survive during metamorphosis, unlike the other larval cells, and finally give rise to the differentiated adult structures. These cells, also known as Adult Progenitor Cells (APCs), maintain their multipotent capacity, differentially respond to hormonal and nutritional signals, survive the intrinsic and environmental stress and respond to the final differentiation cues. However, not much is known about the specific molecular mechanisms that account for their unique characteristics. Here we show that a specificDrosophila APC gene,headcase (hdc), has a dual role in the normal development of these cells. It acts at a systemic level by controlling the hormone ecdysone in the prothoracic gland and at the same time it acts locally as a tissue growth suppressor in the APC clusters, where it modulates the activity of the TOR pathway and promotes their survival by contributing in the regulation of the Unfolded Protein Response. We also show thathdc provides protection against stress in the APCs and that its ectopic expression in cells that do not usually expresshdc can confer these cells with an additional stress protection. Hdc is the founding member of a group of homolog proteins identified fromC.elegans to humans, where has been found associated with cancer progression. The finding that theDrosophila hdc is specifically expressed in progen...
Source: PLoS Genetics - Category: Genetics & Stem Cells Authors: Source Type: research