GALNT3 functions in phosphate homeostasis and bone biology

GALNT3基因的功能突变缺失导致FGF23糖基化不足和随后的蛋白水解，从而导致恶性罗斯托氏综合征或肿瘤钙质沉积症。使用Galnt3 null（^<-/->）小鼠，我们证实了Galnt3在维持活性FGF23中的作用，从而在Pi稳态中发挥作用，并分析了其在骨和睾丸生物学中的功能。我们发现，尽管成骨细胞分化和破骨细胞活性正常，但Galnt3'小鼠的骨体积增加，骨小梁骨伴软骨内含物。GALNT3对精子的产生和成熟也很重要，GALNT3 ^<-/->小鼠的卵黄细胞凋亡证明了这一点。

Loss of function mutations in the GALNT3 gene result in under-glycosylation and subsequent proteolysis of FGF23, leading to hype rostosis-hype rphosphatemi a syndrome or tumoral calcinosis. Using Galnt3 null (^<-/->) mice, we corroborated the roles of GALNT3 in the maintenance of active FGF23, thus in Pi homeostasis and we analyzed its functions in bone and testis biology. We found that Galnt3' mice had increased bone volume and a trabecular bone with cartilage inclusions, despite the facts that osteoblast differentiation and osteoclast activity were normal. GALNT3 is also important for sperm production and maturation, as evidenced by the apoptosis seen in the epydimis of the Galnt3^<-/-> mice.