Lec9 CHO glycosylation mutants are defective in the synthesis of dolichol.
Lec9 CHO glycosylation mutants are defective in the synthesis of dolichol.
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发表时间：
1990-03
影响因子：
6.5
通讯作者：
Anne G. Rosenwald;S. Krag
中科院分区：
文献类型：
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作者：
Anne G. Rosenwald;S. Krag
以前发现Lec9中国仓鼠卵巢细胞在N-连接聚糖的合成中有缺陷。这似乎是寡糖脂质和脂质磷酸盐合成缺陷的结果（Rosenwald，Stanley和Krag. 1989.摩尔cell. 9：914 - 924）。在这项研究中，我们分析了Lec9细胞中长链聚异戊二烯基脂质的稳态水平。我们发现Lec9细胞在合成多萜醇方面存在缺陷。他们积累了一种推测的长萜醇前体，顺式-α-不饱和聚戊烯醇，并将这种脂质用于寡糖脂质的合成。Lec9中活化的聚戊烯醇的链长与亲本细胞中的长醇相同。与亲本细胞相比，Lec9细胞具有增加的单糖基磷酰脂质水平和降低的寡糖基焦磷酸脂水平。Lec 9细胞中的缺陷是多甲醇合成所特有的，因为Lec 9细胞中[3 H]甲羟戊酸代谢的其他方面与亲代细胞相同。我们假设Lec9细胞在聚戊烯醇还原酶活性方面存在缺陷。
Lec9 Chinese hamster ovary cells were found previously to be defective in the synthesis of N-linked glycans. This appeared to be the result of a defect in the synthesis of oligosaccharide lipid and lipid phosphate (Rosenwald, Stanley, and Krag. 1989. Mol. Cell. Biol. 9: 914-924). In this study we analyzed the steady state levels of long-chain polyisoprenyl lipids in Lec9 cells. We found that Lec9 cells are defective in the synthesis of dolichol. They accumulated a presumed precursor to dolichol, cis-a-unsaturated polyprenol and used this lipid in the synthesis of oligosaccharide lipid. Chain lengths of the activated polyprenols in Lec9 were the same lengths as dolichols in parental cells. Lec9 cells had increased levels of monosaccharylphosphoryl lipid and decreased levels of oligosaccharylpyrophosphoryl lipid compared to parental cells. The defect in Lec9 cells was specific for dolichol synthesis, since other aspects of [3H]mevalonate metabolism in Lec9 cells were the same as in parental cells. We hypothesize that Lec9 cells are defective in polyprenol reductase activity.