HUMAN ERYTHROCYTE PROTEIN

人红细胞蛋白

• 批准号: 3472355
• 负责人: anne rybicki
• 金额: $ 8.62万
• 依托单位: MONTEFIORE MEDICAL CENTER (BRONX, NY)
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-04-01 至 1993-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3472355
• 关键词: binding proteins; brain cell; cell population study; chemical binding; chemical stability; chemical structure function; chromatography; crosslink; cytoskeleton; erythrocyte membrane; erythroid stem cell; gel electrophoresis; gene expression; genetic library; hemolytic anemia; human subject; lasers; liposomes; membrane proteins; membrane structure; messenger RNA; molecular biology; molecular pathology; nucleic acid probes; peptide analog; platelets; protein biosynthesis; protein structure; spectrin; tissue /cell culture

All of the major proteins of the human erythrocyte (RBC) membrane except for protein 4.2, have been purified and characterized in great detail. Protein 4.2, which comprises approximately 5% of the total membrane protein, is known to bind to band 3, but its functional role in the membrane cytoskeleton is still largely unknown. We have recently identified an anemic patient whose RBC membranes were selectively deficient in only protein 4.2 (is less than 1% of normal amount of protein 4.2) suggesting that this protein may have an important role in stabilizing the RBC membrane. Our efforts will focus in the following areas: 1) We will determine the membrane binding site(s) for protein 4.2. Although protein 4.2 binds to band 3, recent studies by others have suggested that band 3 is not the only binding site for protein 4.2; 2) we will localize the binding domain of protein 4.2 using the techniques of selective proteolysis and membrane reassociation using purified peptides derived from protein 4.2; 3) we will examine the interaction between purified protein 4.2 and ankyrin's binding to the membrane, recent studies by us have shown that ankyrin binding to protein 4.2-deficient membranes is abnormal; 4) we will examine the structure of protein 4.2 by analyzing one and two-dimensional peptide digests of the purified protein; 5) we will determine the native state of protein 4.2 in situ and examine which other membrane proteins protein 4.2 is in close proximity to in the membrane using in situ crosslinking studies; 6) we will examine non-erythroid cells, such as platelets and brain for the presence of protein 4.2 immunoreactive analogs, preliminary studies suggest that tissue-specific isoforms of protein 4.2 may exist; 7) we will examine the synthesis of protein 4.2 in synchronized erythroid progenitor cells to determine how protein 4.2 stabilizes cytoskeletal assembly; and 8) we will examine the molecular biology of protein 4.2 with a particular emphasis on developing a cDNA probe for this protein. These studies should help to define the properties of protein 4.2 and help us to understand the functional role that protein 4.2 has in stabilizing the RBC membrane cytoskeleton. Since a deficiency of protein 4.2 is associated with RBC pathology, this work may have significant implications for understanding the pathophysiology of certain hemolytic anemias. Furthermore, the ability to probe for the genetic lesion resulting in protein 4.2 deficiency may allow us to recognize heterozygous carriers of this abnormality.

人类红细胞(RBC)的所有主要蛋白质 除蛋白4.2外，膜已被纯化并 具有非常详细的特点。蛋白质4.2，它包括 约有5%的膜蛋白已知结合 到带3，但它在膜细胞骨架中的功能作用是 这在很大程度上仍然是未知的。我们最近发现了一名贫血患者 仅红细胞膜选择性缺陷的患者 蛋白质4.2(低于正常蛋白质4.2含量的1%) 这表明这种蛋白质可能在 稳定红细胞膜。 我们的努力将集中在以下几个方面：1)我们将 确定蛋白4.2的膜结合位点(S)。虽然 蛋白质4.2结合到带3，最近其他人的研究已经 提示带3不是蛋白4.2的唯一结合位点； 2)我们将使用 选择性蛋白分解和膜再解离技术 使用从蛋白质4.2中提取的纯化多肽；3)我们将 检测纯化蛋白4.2与锚定蛋白的相互作用 结合到膜上，我们最近的研究表明 锚蛋白与蛋白4.2缺乏的膜结合异常； 4)我们将通过分析一个蛋白质4.2的结构 和纯化蛋白的二维肽酶切；5)我们 将在原位测定蛋白质4.2的天然状态并检查 Protein 4.2还接近哪些其他膜蛋白 在膜中使用原位交联剂的研究；6)我们将 检查非红系细胞，如血小板和脑 蛋白4.2免疫反应类似物的存在，初步 研究表明，组织特异性蛋白4.2的亚型可能 存在；7)我们将研究蛋白质4.2在 同步的红系祖细胞以确定蛋白质如何 4.2稳定细胞骨架组装；和8)我们将检查 蛋白质4.2的分子生物学，特别强调 开发一种针对该蛋白的cDNA探针。这些研究应该 帮助定义蛋白质4.2的性质，并帮助我们 了解蛋白质4.2在稳定环境中的功能作用 红细胞膜细胞骨架。因为缺乏蛋白质 4.2与红细胞病理有关，这项工作可能有 对理解心绞痛的病理生理学有重要意义 某些溶血性贫血。此外，能够探测到 导致蛋白质4.2缺乏的遗传损伤可能会使我们 以识别这种异常的杂合子携带者。