Clonal analysis of compensatory proliferation in dmHexDC mutants

Abstract

Recycling of sugar-containing organic compounds (saccharides) have importance for metabolic activity, cellular growth, and differentiation. During this recycling process, many enzymes, primarily lysosomal enzymes, play a role. We have discovered a novel hexosaminidase enzyme in Drosophila, dmHexDC that may have a role in ganglioside and glycosaminoglycan recycling. The function of dmHexDC was investigated in apoptosisinduced compensatory proliferation pathway in retinal development in Drosophila melanogaster. As a result of this study, we show that lack of dmHexDC induces autophagy, which might trigger programmed cell death. Furthermore, we demonstrate by clonal analysis that in dmHexDC deficiency, compensatory proliferation mechanism is activated in neighboring cells. Defects of neuronal differentiation and glial migration were determined especially in the Notch-active equatorial region. Subcellular localization studies indicate that dmHexDC is localized mainly to the ER. Overall, our results indicate that dmHexDC plays a crucial role in Drosophila eye development and cell differentiation.