缺陷的GALNT3导致HFTC
中文名称
通路描述
UDP GalNAc：多肽N乙酰基半乳糖胺转移酶（GalNAc转移酶，GALNTs）家族执行在蛋白质上添加N乙酰基半乳糖胺（GalNAc）的反应，该反应发生在血清、丝氨酸、苏氨酸或可能酪氨酸残基上，最常见的是与黏膜相关。这是GalNAc型O连接寡糖生物合成的初始反应（Wandall et al. 1997）。该反应发生在高尔基体（Rottger et al. 1998）。GALNT家族已知有20个成员，其中15个已表征，5个候选成员基于序列相似性被认为属于该家族（Bennett et al. 2012）。GALNT家族分类为CAZy家族GT27。GALNT家族基因中的一个缺陷，GALNT3（MIM:601756），可导致家族性高磷血症性肿瘤钙化症（HFTC; MIM:211900）。HFTC是一种罕见的常染色体隐性严重代谢疾病，其特征是钙磷酸盐晶体在皮肤、软组织和有时骨骼中的渐进性沉积（Chefetz et al. 2005）。生化观察是高磷血症，由肾磷吸收增加引起（Chefetz et al. 2005, Ichikawa et al. 2005）。一些患者表现出反复、短暂的、疼痛的长骨肿胀，影像学证据显示骨膜反应和骨皮质增生（Frishberg et al. 2005）。
英文描述
Defective GALNT3 causes HFTC The family of UDP GalNAc:polypeptide N acetylgalactosaminyltransferases (GalNAc transferases, GALNTs) carry out the addition of N acetylgalactosamine (GalNAc) on serine, threonine or possibly tyrosine residues on a wide variety of proteins, most commonly associated with mucins. This is the initial reaction in the biosynthesis of GalNAc-type O linked oligosaccharides (Wandall et al. 1997). This reaction takes place in the Golgi apparatus (Rottger et al. 1998). There are 20 known members of the GALNT family, 15 of which have been characterised and 5 candidate members which are thought to belong to this family based on sequence similarity (Bennett et al. 2012). The GALNT-family is classified as belonging to CAZy family GT27. Defects in one of the GALNT family genes, GALNT3 (MIM:601756), can cause familial hyperphosphatemic tumoral calcinosis (HFTC; MIM:211900). HFTC is a rare autosomal recessive severe metabolic disorder characterised by the progressive deposition of calcium phosphate crystals in the skin, soft tissues and sometimes bone (Chefetz et al. 2005). The biochemical observation is hyperphosphatemia, caused by increased renal absorption of phosphate (Chefetz et al. 2005, Ichikawa et al. 2005). Some patients manifest recurrent, transient, painful swellings of the long bones with radiological evidence of periosteal reaction and cortical hyperostosis (Frishberg et al. 2005).
所含基因
18 个基因