Cellular retinol-binding protein I is essential for vitamin A homeostasis
Cellular retinol-binding protein I is essential for vitamin A homeostasis
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DOI：
10.1093/emboj/18.18.4903
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发表时间：
1999-09-15
期刊：
影响因子：
11.4
通讯作者：
Chambon, P
中科院分区：
文献类型：
--
作者：
Ghyselinck, NB;Båvik, C;Chambon, P
编码细胞视黄醇（ROL，vitA）结合蛋白I型（CRBPI）的基因已失活。喂食富含维生素饮食的突变小鼠健康且能生育。它们不存在任何与维甲酸（RA）缺乏相关的先天性异常，表明CRBPI不是RA合成所必需的，然而，CRBPI缺乏导致肝星状细胞中视黄酯（RE）积累减少约50%。这种减少是由于减少的合成和6倍更快的营业额，这是不相关的RE代谢酶的水平的变化，但可能反映了受损的交付ROL卵磷脂：视黄醇酰基转移酶。CRBPI缺失的小鼠喂养维生素缺乏的饮食5个月完全耗尽他们的RE商店。因此，CRBPI是有效的RE合成和储存不可或缺的，它的缺乏导致ROL的浪费，这在维生素A充足的动物中是无症状的，但在喂食维生素A缺乏饮食的动物中导致严重的维生素A缺乏综合征。
The gene encoding cellular retinol (ROL, vitA)-binding protein type I(CRBPI) has been inactivated. Mutant mice fed a vitA-enriched diet are healthy and fertile. They do not present any of the congenital abnormalities related to retinoic acid (RA) deficiency, indicating that CRBPI is not indispensable for RA synthesis, However, CRBPI deficiency results in an similar to 50% reduction of retinyl ester (RE) accumulation in hepatic stellate cells. This reduction is due to a decreased synthesis and a 6-fold faster turnover, which are not related to changes in the levels of RE metabolizing enzymes, but probably reflect an impaired delivery of ROL to lecithin:retinol acyltransferase. CRBPI-null mice fed a vitA-deficient diet for 5 months fully exhaust their RE stores. Thus, CRBPI is indispensable for efficient RE synthesis and storage, and its absence results in a waste of ROL that is asymptomatic in vitA-sufficient animals, but leads to a severe syndrome of vitA deficiency in animals fed a vitA-deficient diet.