视黄酸对人肝癌细胞表面N糖链类型及天线数的影响

Effect of Retinoic Acid on the Type and Antennary Number of N-Linked Oligosaccharide on the Surface of Human Hepatocarcinoma Cells

本文采用系列凝集素柱层析法，并配合外切糖苷酶处理研究了在视黄酸作用１－５天过程中人肝癌细胞株ＳＭＭＣ－７７２１细胞表面Ｎ糖结构的变化。结果表明，ＲＡ促进＾３Ｈ－甘露糖参入细胞表面Ｎ糖链，使高甘露糖型Ｎ糖的百分比下降，复杂型百分比长升，并促进二天线Ｎ糖链的生物合成，使多天线特别是四天线和Ｃ２，Ｃ２１ｂ三天线Ｎ糖链的合成减少。结果提示。

~3H-mannose labeled N-linked oligosaccharides were prepared from the cell surface of human hepatocarcinoma cell line SMMC-7721 treated with retinoic acid (RA) for 1—5 days and compared with untreated control cells by serial lectin affinity chromatography combined with exoglycosidase treatment. The results showed that RA stimulated incorporation of ~3H-mannose into N-linked oligosaccharides on the cultured cell surface, decreased the percentage of high mannose type, and increased the percentage of complex type. Moreover, RA accelerated the biosynthesis of biantennary complex type, but decelerated the biosynthesis of tetraantennary and trianternnary, espically C_2,C_(2,6) triantennary complex type N- linked oligosaccharides. It is suggested that the structural changes of N-linked oligosaccharides are associated with the Cell differentiation induced by retinoic acid.