Cellular functions of a cytosolic glycerophosphocholine phosphodiesterase GDE5

点击翻译按钮获取中文摘要

We previously showed that GDE5 is a cytosolic glycerophosphocholine (GPC) phosphodiesterase. Here, we characterized the cellular functions of GDE5 in adipocytes because GDE5 expression is highly expressed during 3T3-L1 adipocyte differentiation. Knockdown of endogenous GDE5 in 3T3-L1 adipocytes dramatically suppressed adipocye differentiation, unexpectedly, through a modulation of the mitotic clonal expansion. Decreasing GDE5 abundance resulted in a marked increase in intracellular GPC level. We showed that decreasing GDE5 expression significantly upregulated mRNA expression of proteoglycans such as lumican, and decorin in 3T3-L1 cells. These results suggest that decreasing GDE5 abundance caused osmotic imbalance by the intracellular GPC accumulation and inhibited the mitotic clonal expansion of adipocytes. These provide an insight into the novel roles of GDE5 in osmotic balance which depends on GPC phosphodiesterase activity.