INTRACELLULAR PROTEIN CATABOLISM IN DIABETES MELLITUS

这项研究的长期目标是阐明机制。 细胞内蛋白质分解代谢的研究进展及细胞内蛋白质的作用 蛋白酶在调节健康和疾病中的细胞事件中的作用 比如糖尿病。我的方法一直是确定和 细胞蛋白水解酶的特性和生物利用的机制 降解细胞蛋白质的系统，并确定 控制特定酶的降解速度 有机体的新陈代谢需求。这项工作提供了 关于MEPRIPS结构和活动的基本信息， 和一个新的金属内肽酶家族，并已扩展到 包括对生物合成、加工和激活的研究 哺乳动物细胞表面蛋白水解酶，以及可能适用于 肾功能衰竭和疾病。在下一阶段，建议 调查：(A)推动共价和 Meprin亚基的非共价结合形成活性和 潜伏的同源和异源低聚物与多聚体之间的关联 与其他膜、内质网和胞浆蛋白。 使用的方法包括对重组人的突变分析 在人293细胞中表达的meprin亚基的测量 酶的活性、稳定性和寡聚化，以及 用酵母双杂交系统评估相互作用单位。 (B)meprint通过破坏结构基因发挥作用 亚基，检测亚基的胚胎表达， 并通过确定成年小鼠的高和低meprin A是否 表型对肾脏的压力有不同的反应。尿液 人类甲氨蝶呤的形式也将被表征，并且 成人基因表达具有多态的命题 将检查meprinα亚单位，小鼠也是如此。梅普林斯有 为研究细胞表面的调控提供了一个很好的模型 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 这些膜结合和分泌的蛋白水解酶以及 关于发育、成熟、 以及疾病缠身的州。

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.