根据mRNA转录子的大小,β-1,4-半乳糖基转移酶分为短型和长型两类半乳糖基转移酶.短型的位于高尔基体的成熟面.长型的主要表达在细胞表面,通过与相邻细胞表面或细胞外基质上的适当的糖苷底物的结合介导细胞-细胞和细胞-基质间的相互作用,如精子发生、精卵结合、早期胚胎细胞间粘附、次生滋养层巨细胞迁移和神经轴突向外生长等,或作为胞外寡糖链配基的信号传递受体影响G蛋白信号途径.另外,表面半乳糖基转移酶通过调节表皮生长因子受体信号传导能力向胞内传递生长抑制信号,在细胞增殖控制中起重要作用.
β-1,4-galactosyltransferase (GalTase) can be divided into short and long forms by its mRNA. The short form GalTase within the trans-Golgi compartment participates in the biosynthesis of glycoconjugates. The long form on cell surface mediates cell-cell and cell-matrix interactions by binding to appropriate glycoside substrates on adjacent cell surfaces or in the extracellular matrix, including spermatogenesis, sperm-egg binding, early embryo cell adhesion, secondary trophoblast giant cell migration and neurite outgrowth, and functions as a signal-transducing receptor for extracellular oligosaccharide ligands to affect G protein signal cascades. Surface GalTase also delivers a growth inhibitory signal by modulating the ability of the EGF receptor to transduce EGF-dependent signals, and plays an important role during cell growth.
张春雨,段恩奎,曾国庆,刘以训.细胞表面半乳糖基转移酶及其生物学功能[J].生物化学与生物物理进展,1997,24(6):518-520
复制生物化学与生物物理进展 ® 2024 版权所有 ICP:京ICP备05023138号-1 京公网安备 11010502031771号