Marino M, Leoni S, Spagnuolo S, Conti Devirgiliis L, Mangiantini M T
Dipartimento di Biologia Cellulare e dello Sviluppo, Università di Roma La Sapienza, Roma, Italy.
Biosci Rep. 1989 Oct;9(5):565-72. doi: 10.1007/BF01119799.
The aim of the present report was to analyze the pattern of glycoprotein synthesis in rat liver on 19th and 22nd day of pregnancy by following the incorporation of 14C-glucosamine and 3H-galactose into isolated rat hepatocytes, the N-acetylglucosaminyl-1-P and galactosyl transferase activities, and the liver content of dolichol and dolichyl-phosphate. The data obtained show a decrease of precursor incorporation into glycoproteins during the last period of pregnancy; this decrease is independent of enzyme activities. The dolichol content increases and the dolichyl-phosphate content, usually considered as rate limiting for glycosylation, decreases. These results, present in other conditions of proliferation and differentiation of rat liver, could explain the differences in membrane organization, the increase of hepatic proteolysis and the alteration in secretory activity during the last phase of gestation.
本报告的目的是通过追踪14C-葡萄糖胺和3H-半乳糖掺入分离的大鼠肝细胞的情况、N-乙酰葡糖胺-1-P和半乳糖基转移酶活性以及肝脏中多萜醇和多萜醇磷酸酯的含量，分析妊娠第19天和第22天大鼠肝脏中糖蛋白合成的模式。获得的数据显示，在妊娠后期前体掺入糖蛋白的情况减少；这种减少与酶活性无关。多萜醇含量增加，而通常被认为是糖基化限速因素的多萜醇磷酸酯含量减少。这些在大鼠肝脏增殖和分化的其他条件下也存在的结果，可以解释妊娠后期膜组织的差异、肝脏蛋白水解的增加以及分泌活性的改变。
