INTRACELLULAR PROTEIN CATABOLISM IN DIABETES MELLITUS

这项研究的长期目标是阐明 细胞内蛋白质催化剂和细胞内的作用 蛋白酶在健康和疾病细胞事件中的调节作用 例如糖尿病。我的方法是识别和 表征细胞蛋白酶和机制使用的生活 降解细胞蛋白质的系统，并确定 控制特定酶的降解速率， 有机体的代谢需求。这项工作提供了 关于meprins的结构和活性的基本信息， 和一个新的金属内肽酶家族，并已扩展到 包括生物合成，加工和激活的研究， 细胞表面的哺乳动物蛋白酶，并适用于领域， 肾衰竭和疾病。在下一阶段，建议 研究：（A）驱动共价键的因素和基序， meprin亚基的非共价结合形成活性和 潜在的同源和异源寡聚体，以及meprins的关联 与其他膜、内质网和胞质蛋白质结合。 使用的方法包括重组的突变分析。 在人293细胞中表达的meprin亚基， 酶的活性、稳定性和寡聚化，和 使用酵母双杂交系统评估相互作用单位。 (B)meprins的功能，通过破坏结构基因， 亚基，检查亚基的胚胎表达， 并通过测定高和低meprin A的成年小鼠 表型对肾脏的应激反应不同。尿 还将表征人甲氨蝶呤的形式， 主张成人是多态的表达， 将检查与小鼠一样的甲氧苄氨嘧啶α亚基。梅普林人 为研究细胞表面的调控提供了一个极好的模型 蛋白酶这些研究将提供基本信息 关于生物合成、相互作用、调节和功能<）f 这些膜结合和分泌的蛋白酶，以及 关于发育，成熟， 和病态的国家

The long-range goals of this research are to elucidate mechanisms of intracellular protein catabolism and the role of cellular proteinases in mediation of cellular events in health and diseases such as diabetes mellitus. My approach has been to identify and characterize cellular proteinases and mechanisms used by living systems to degrade cellular proteins, and to determine factors that control the rate of degradation of specific enzymes according to the metabolic needs of the organism. The work has provided fundamental information about structure and activity of meprins, and a-new family of metalloendopeptidases, and has expanded to include studies of the biosynthesis, processing, and activation of cell-surface mammalian proteinases, and to areas that may apply to renal failure and disease. In the next period, it is proposed to investigate: (A) factors and motifs that drive the covalent and non-covalent association of meprin subunits to form active and latent homo- and heterooligomers, and the association of meprins with other membrane, endoplasmic reticulum, and cytosolic proteins. Methods to be used include mutational analyses of recombinant meprin subunits expressed in human 293 cells, measurements of activity, stability, and oligomerization of the enzymes, and assessment of interacting units using the yeast two-hybrid system. (B) the function of meprins by disrupting the structural genes for the subunits, examining the embryonic expression of the subunits, and by determining whether adult mice with high and low meprin A phenotypes react differently to stresses on the kidney. Urinary forms of human meprin will also be characterized, and the proposition that adults are polymorphic for expression of the meprin alpha-subunit, as are mice, will be examined. Meprins have provided an elegant model to study the regulation of cell surface proteinases. These studies will provide fundamental information about the biosynthesis, interactions, regulation, and functions <)f these membrane-bound and secreted proteinases, as well as information about isoforms of the enzymes in developmental, mature, and diseased states.