DIFFERENTIAL REGULATION OF GLUCOSE TRANSPORTER ISOFORMS

葡萄糖转运蛋白异构体的差异调节

• 批准号: 3464793
• 负责人: MARTYN K WHITE
• 金额: $ 8.1万
• 依托单位: EAST CAROLINA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-30 至 1997-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3464793
• 关键词: animal tissue; chickens; chimeric proteins; gene deletion mutation; genetic regulation; genetic transcription; glucose transport; immunoelectron microscopy; membrane proteins; nucleic acid sequence; oncogenes; protein biosynthesis; protein degradation; protein structure function; regulatory gene; transport proteins

The rate of glucose uptake into vertebrate cells is regulated by oncogenic transformation and by many other factors including mitogen, hormones and glucose starvation. It has been shown that regulation of glucose transporters can occur at different levels including transcription, mRNA stability, protein translocation and protein turnover. Glucose transporters provide a way of studying cellular regulation at these levels as well as the relationship of growth control to carbohydrate metabolism. In addition there are five transporter isoforms which are regulated differently, thus providing a useful model system for understanding how isoforms are regulated according to the metabolic needs of the cell. We are interested in chicken embryo fibroblasts since they express at least two glucose transporter isoforms and these are differentially regulated (type 1 is regulated by protein turnover and type 3 by the level of its mRNA). The goals of this proposal are to understand the molecular basis of this differential regulation. AIM 1: We propose to complete the cloning and sequencing of the cDNAs of glucose transporter isoforms expressed by chicken embryo fibroblasts. AIM 2: These will be used to measure the levels of the mRNAs for each isoform under various physiological conditions. The rate of transcription for each isoform and stability of its mRNA will also be measured. AIM 3: The molecular basis for the differential transcriptional control of the transporter isoforms will be determined by isolating genomic clones and analyzing their promoter regions. AIM 4: The control of transporters at the protein level will be investigated by generating specific antisera to each isoform. These will be used to quantitate the level of each isoform under various physiological conditions and to measure their rates of biosynthesis and turnover. It has already been established that the type 1 isoform is regulated at the level of turnover. AIM 5: Cellular and biochemical analysis of the molecular basis of this turnover control will be undertaken. This study will provide basic information about the regulation of different isoforms and about several levels of cellular control.

脊椎动物细胞摄取葡萄糖的速率受致癌物质的调节 转化以及许多其他因素，包括丝裂原、激素和 葡萄糖饥饿。 研究表明，葡萄糖的调节 转运蛋白可以发生在不同的水平，包括转录、mRNA 稳定性、蛋白质易位和蛋白质周转。 葡萄糖 转运蛋白提供了一种研究这些水平的细胞调节的方法 以及生长控制与碳水化合物代谢的关系。 此外，还有五种受监管的转运蛋白亚型 不同地，从而提供了一个有用的模型系统来理解如何 同种型根据细胞的代谢需要进行调节。 我们 对鸡胚成纤维细胞感兴趣，因为它们至少表达 两种葡萄糖转运蛋白亚型，它们受到不同的调节 （1 型受蛋白质周转调节，3 型受其蛋白质水平调节） mRNA）。 该提案的目标是了解 这种差异化监管。 目标 1：我们建议完成 cDNA 的克隆和测序 鸡胚成纤维细胞表达的葡萄糖转运蛋白亚型。 目的 2：这些将用于测量每种亚型的 mRNA 水平 在各种生理条件下。 每个的转录率 还将测量其 mRNA 的亚型和稳定性。 目标 3： 差异转录控制的分子基础 转运蛋白亚型将通过分离基因组克隆来确定 分析它们的启动子区域。 目标 4：运输者的控制 将通过产生特异性抗血清来研究蛋白质水平 每个亚型。 这些将用于定量每种亚型的水平 在不同的生理条件下并测量它们的速率 生物合成和周转。 已经确定该类型 1 同工型在周转水平上受到调节。 目标 5：蜂窝和 对这种周转控制的分子基础进行生化分析将 进行。 本研究将提供有关的基本信息 不同异构体和细胞多个水平的调节 控制。