DOLICHOL PHOSPHATE METABOLISM AND GLYCOPROTEIN SYNTHESIS

磷酸多醇代谢和糖蛋白合成

• 批准号: 3289671
• 负责人: Charles J Waechter
• 金额: $ 15.8万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-06-01 至 1992-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3289671
• 关键词: B lymphocyte; cell differentiation; cell growth regulation; dolichol; enzyme mechanism; glycosylation; human tissue; immunoglobulins; ionomycin; laboratory mouse; lipopolysaccharides; phosphoric ester; protein biosynthesis; protein kinase C; tritium

The activation of B-lymphocytes (B-cells) leads to increased synthesis of membrane-bound and secretory glycoproteins. This application proposes studies on the regulation of N-glycosylation activity when membrane glycoprotein synthesis is stimulated in resting B-cells induced to proliferate by bacterial lipopolysaccharide (LPS). The control of N-glycosylation will also be investigated in the human B lymphoblastoid cell line (CESS) stimulated to differentiate and secrete large amounts of immunoglobulins by exposure to B-cell differentiation factor (BCDF). Changes in N-glycosylation activity in response to the induction of proliferation or differentiation of the B-cells will be correlated with changes in several enzymes involved in dolichyl phosphate (Do1-P) metabolism and the synthesis of dolichol-linked oligosaccharides. Dolichol kinase and Dol-P phosphatase activity will be assayed in vitro to determine if Dol-P levels could be altered by shifting the balance in a phosphorylation- dephosphorylation scheme during the proliferation of B-cells or the differentiation of the CESS line. The requirement for de novo synthesis of dolichol or Dol-P during the proliferative and differentiative changes will be explored by metabolic labeling experiments with (3H)mevalonate, and studies with exogenously supplied dolichol and capactin, the competitive inhibitor of HMG- CoA reductase. The possible involvement of Ca++-mobilization and protein kinase C in the activation processes will be explored by cellular studies with ionomycin and phorbol diesters. The proposed experiments could shed new light on the control of the N-glycosylation apparatus in B-cells, and extend the current knowledge of the biochemical events occurring during the proliferation and differentiation of B-lymphocytes.

B淋巴细胞的激活（B细胞）导致增加 膜结合和分泌糖蛋白的合成。 这 应用提出了关于N-糖基化调节的研究 当刺激膜糖蛋白合成时的活性 静止的B细胞被细菌诱导 脂多糖（LPS）。 N-糖基化的控制也将 在人类B淋巴细胞细胞系（CESS）中进行研究 刺激以区分和分泌大量 通过暴露于B细胞分化因子的免疫球蛋白 （BCDF）。 响应于N-糖基化活性的变化 诱导B细胞的增殖或分化将是 与涉及多乙基的几种酶的变化相关 磷酸盐（DO1-p）代谢和与多利基醇连接的合成 寡糖。 多利乔尔激酶和DOL-P磷酸酶活性 将在体外测定以确定DOL-P水平是否可以 通过在磷酸化中移动平衡而改变 在B细胞增殖期间的去磷酸化方案或 CESS线的差异化。 从头开始的要求 在增殖过程中合成多利醇或dol-p的合成 代谢标签将探索区分变化 （3H）甲戊酸的实验，并进行外源研究 提供的Dolichol和Capactin是HMG-的竞争抑制剂 COA还原酶。 CA ++的可能参与 - 动员 将探索激活过程中的蛋白激酶C 通过用离子霉素和佛波尔·戴斯特斯进行细胞研究。 这 提出的实验可以为控制 B细胞中的N-糖基化设备，并扩展电流 了解在此期间发生的生化事件 B淋巴细胞的增殖和分化。