Chen H L, Dong S C, Ju T Z, Yang X P
Key Laboratory of Glycoconjugates Shanghai Medical University, China.
J Cancer Res Clin Oncol. 1995;121(7):397-401. doi: 10.1007/BF01212945.
In order to study the effect of retinoic acid on the structure of N-glycans on the cell surface, the N-glycans of glycoproteins on the surface of 7721 human hepatocarcinoma cells were labelled with [3H] mannose, added to the culture medium. The 3H-labelled N-glycans were prepared from cell-surface glycoproteins, desialylated, and subjected to sequential chromatography on concanavalin A and Datura stranonium agglutinin affinity columns to separate the glycans into four fractions of different type and different antennary number. It was found that the percentage of C2C2 biantennary complex type N-glycans was increased, but the high-mannose type as well as the tri- and tetraantennary complex types, especially that with a C2.6 branched structure, were decreased after the cells had been treated with retinoic acid for 3-5 days. Using a Lens culinaris agglutinin affinity column, it was discovered that the core fucose in the biantennary glycan was also decreased. The enzymatic mechanisms of the above changes were revealed in further study to involve the decrease of N-acetylglucosaminyl-transferase V and core alpha-1,6-fucosyltransferase by retinoic acid.
为了研究视黄酸对细胞表面N-聚糖结构的影响，将添加到培养基中的[3H]甘露糖标记7721人肝癌细胞表面糖蛋白的N-聚糖。从细胞表面糖蛋白制备3H标记的N-聚糖，去唾液酸化，然后在伴刀豆球蛋白A和曼陀罗凝集素亲和柱上进行连续层析，将聚糖分离成四种不同类型和不同天线数的组分。结果发现，经视黄酸处理3-5天后，C2C2二天线复合型N-聚糖的百分比增加，但高甘露糖型以及三天线和四天线复合型聚糖，特别是具有C2.6分支结构的聚糖减少。使用扁豆凝集素亲和柱发现，二天线聚糖中的核心岩藻糖也减少。进一步研究揭示了上述变化的酶促机制，包括视黄酸导致N-乙酰葡糖胺转移酶V和核心α-1,6-岩藻糖基转移酶减少。
