Cells in multi-cellular eukaryotes, though sharing the same genetic information, emerge as different cell types. This cell fate determination, achieved early on in Drosophila development, is established by the differential gene expression controlled by the evolutionary conserved Trithorax group (TrxG) and Polycomb group (PcG) genes. The faithful transfer of cell specific gene expression pattern to the descendent cells is mediated by epigenetic mechanisms such as DNA methylation, chromatin remodeling and histones modifications and is such referred to as epigenetic transcriptional cellular memory. PcG mediates gene silencing while TrxG works antagonistically by maintaining gene activation. Despite extensive studies, the molecular action and regulation of TrxG in relation to cell signaling components is still not clearly known. The aim of this study will be to characterize CG10376, a phosphatase that has the potential to facilitate TrxG-mediated gene activation. Identified as a possible TrxG regulator through a genome wide RNAi screen preformed in our laboratory, CG10376 encodes a Mg2+/Mn2+-dependent serine/threonine phosphatase. Results of molecular analysis have indicated that this uncharacterized protein is pre-dominantly expressed in the cytoplasm. In-vitro RNAi studies of CG10376 has shown that knockdown of CG10376 significantly downregulates the expression Pnt Pnr and Psq, the non-homeotic targets of TrxG, hence highlighting its potential role as a TrxG regulator.