L-serine regulation of RANK signaling machinery and its role in bone metabolism

破骨细胞在骨的发育和重建中起着重要作用。除了RANKL的刺激外，培养基中的丝氨酸对于破骨细胞从其前体的体外分化是必需的。我们进行了一系列的实验来了解丝氨酸对破骨细胞分化的调控机制及其生理意义，发现丝氨酸转运与细胞对其他氨基酸的摄取之间存在关联，丝氨酸剥夺通过减少细胞内其他几种氨基酸和下调RANKL受体RANK来抑制破骨细胞的分化。

Osteoclasts play central roles in the development and remodeling of bone. In addition to the stimulation by RANKL, serine in the culture medium is necessary for the in vitro differentiation of osteoclasts from their precursors. We conducted a series of experiments to understand the regulatory mechanism of osteoclast differentiation by serine as well as its physiological significance, and found the association between serine transport and cellular uptake of other amino acids and serine deprivation suppresses the differentiation through the reduction of other several intracellular amino acids and the downregulation of RANKL receptor, RANK.