Lysosomal Enzymes and Associated Human Genetic Diseases

描述(由申请人提供)： 溶酶体是酸性的、膜分隔的细胞器，其中心功能是降解大分子。溶酶体含有多种可分解底物的可溶酶，以及执行多种功能的跨膜蛋白，包括将降解产物运输出细胞器。溶酶体蛋白在正常细胞生理中的重要性在几十种溶酶体储存障碍(LSD)中得到了证明，例如泰-萨奇病，其中单一溶酶体蛋白的缺乏会导致分解代谢物的积累和下游代谢物的耗尽。这些单基因疾病通常会导致严重的疾病，包括智力低下、发育畸形和过早死亡。已发现40多种不同LSD的基因缺陷，通过遗传咨询，极大地降低了其中一些疾病的患病率。尽管取得了这一令人印象深刻的进展，但仍有许多工作要完成，因为有一些临床定义的疾病似乎是LSD，但其分子病因尚不清楚。此外，还有许多基于临床和超微结构标准的LSD患者的基因缺陷尚未确定。我们推测，许多这些未解决的遗传性疾病是由编码溶酶体蛋白的基因突变引起的。这项提案的总体目标是确定这些未侦破的LSD案件的依据。有两个具体目标。目的1是使用一种新开发的比较蛋白质组学方法来鉴定异常蛋白和导致大量未解决的LSD的基因缺陷。目标2是使用亚细胞分离的定量质谱学来定义溶酶体蛋白质组，并使生物医学界能够容易地获得这些信息。这将建立一个资源，这将极大地促进使用其他方法，如连锁分析来鉴定溶酶体疾病基因。完成这些特定目标将识别新的溶酶体疾病基因以及导致非典型临床表现的现有疾病基因的新突变。这将对受影响的个人和家庭具有极其重要的意义，并将提供有关溶酶体缺陷如何表现的重要信息。此外，为研究LSD而建立的蛋白质组学方法将使未来能够对溶酶体变化可能很重要的广泛的人类疾病进行研究，包括癌症和阿尔茨海默病。最后，溶酶体蛋白质组的分配将是对功能基因组学的重要贡献，并将产生广泛的生物医学影响。这项研究还将建立系统，调查一组生物医学上重要的蛋白质在阿尔茨海默氏症和癌症等广泛传播的人类疾病中的作用。

DESCRIPTION (provided by applicant): Lysosomes are acidic, membrane-delimited organelles whose central function is to degrade macromolecules. The lysosome contains a wide variety of soluble enzymes that hydrolyze substrates as well as transmembrane proteins that perform a number of functions including transport of degradation products out of this organelle. The importance of lysosomal proteins in normal cellular physiology is illustrated by the dozens of lysosomal storage disorders (LSDs) such as Tay-Sach's disease where a deficiency in a single lysosomal protein results in accumulation of catabolites and a depletion of downstream metabolites. These monogenic diseases typically cause severe illness including mental retardation, developmental deformities, and premature death. The gene defects in over 40 different LSDs have been identified, which, through genetic counseling, has greatly decreased the prevalence of some of these disorders. Despite this impressive progress, much remains to be accomplished as there are a number of clinically-defined disorders that appear to be LSDs but which are of unknown molecular etiology. In addition, there are numerous individuals that have LSDs based upon clinical and ultrastructural criteria for which the gene defects have not been identified. We hypothesize that many of these unsolved genetic diseases are caused by mutations in genes encoding lysosomal proteins. The overall goal of this proposal is to determine the basis of these unsolved LSD cases. There are two specific aims. Aim 1 is to use a newly developed comparative proteomics method to identify aberrant proteins and the gene defects underlying numerous unsolved LSDs. Aim 2 is to use quantitative mass spectrometry with subcellular fractionation to define the lysosomal proteome and to make this information readily accessible to the biomedical community. This will establish a resource that will greatly facilitate identification of lysosomal disease genes using other approaches such as linkage analysis. Completion of these specific aims will identify new lysosomal disease genes as well as new mutations in existing disease genes that cause atypical clinical presentations. This will be of paramount significant to the affected individuals and families, and will provide important information on how lysosomal deficiencies are manifested. In addition, the proteomics methods established to investigate LSDs will enable future studies on widespread human disorders where lysosomal changes may be important, including cancer and Alzheimer disease. Finally, assignment of the lysosomal proteome will be an important contribution to functional genomics and will have broad biomedical impact.The proposed research is to determine the basis for previously unsolved human genetic diseases. This research will also establish systems for the investigation of the role of a group of biomedically important proteins in widespread human diseases in such as Alzheimer's and cancer.