RUI: Investigating the mechanisms regulating the formation of lysosome-related organelles

该项目将研究在多细胞动物中，在某些细胞类型而不是其他细胞类型中是如何产生隔室的。复杂生物体的细胞含有称为细胞器的隔室，这些隔室赋予细胞特定的功能特性。虽然许多细胞器对生物体内的所有细胞都是共同的，但有些细胞器仅在细胞类型的子集中产生。其中一种被称为溶酶体相关细胞器（LRO），发挥着多种重要作用，但只有某些动物细胞产生它们。这项研究将调查这是如何实现的，并确定促进LROs形成的因素。许多本科生（25-55人/年）将在合作、调查和原创研究方面受到指导，作为项目的一部分。其中许多学生将来自科学界代表性不足的群体。这项工作将为大批不同类型的学生提供实际的科学培训，他们中的大多数人将在科学和教育领域取得进展。在许多细胞类型中，溶酶体相关细胞器LROs与传统溶酶体共存，这是由于保守的lro特异性运输途径的活性将货物从内溶酶体转移。LRO生物发生途径的出现可能是由于所有细胞中表达的一般内溶酶体运输因子与仅在含LRO细胞中存在并活跃的关键调节因子之间的相互作用知之甚少。为了鉴定和研究这些调节因子的功能，该项目正在分析秀丽隐杆线虫肠道颗粒的生物发生，细胞类型特异性LROs与传统溶酶体共存。在该系统中发现的一些LRO生物发生因子具有细胞类型限制性表达，并可能调节货物向LRO的转移。该研究解决了其中一个，GLO-3的功能，该功能被提出将CCZ-1（一种Rab -7鸟嘌呤核苷酸交换因子（GEF））的功能从传统的内溶酶体途径转移到GLO-1 Rab以调节LRO的生物发生。该研究将包括突变体的详细表型分析、酵母2杂交筛选和体外GEF分析。该研究将检验表达GLO-3和其他LRO生物发生因子是否足以引导LRO货物从通常不产生LRO的细胞类型的传统内体中运输。该研究将利用一种新的遗传资源来鉴定秀丽隐杆线虫LRO生物发生所需的几乎所有基因。

The project will investigate how compartments are generated within some cell types but not others in multicellular animals. The cells of complex organisms contain compartments called organelles that endow cells with their specific functional properties. While many organelles are common to all of the cells within an organism, some are only generated in a subset of cell types. One of these, called a lysosome-related organelle (LRO), plays varied and important roles, however only certain animal cells generate them. The research will investigate how this is achieved and identify factors that promote the formation of LROs. Many undergraduates (25-55/year)will be mentored in collaborative, investigative, and original research as part of the project. Many of these students will come from underrepresented groups in the sciences. The work will provide hands on scientific training for a large and diverse group of students, most of who will progress on to careers in science and education.In many cell types, lysosome-related organelles LROs co-exist with conventional lysosomes due to the activity of conserved LRO-specific trafficking pathways that divert cargo away from endolysosomes. The emergence of LRO biogenesis pathways likely result from the poorly understood interplay of general endolysosome trafficking factors expressed in all cells with key regulators that are only present and active within LRO-containing cells. To identify and investigate the function of these regulators, the project is analyzing the biogenesis of C. elegans gut granules, cell type-specific LROs that co-exist with conventional lysosomes. Some LRO biogenesis factors identified in this system have cell type restricted expression and likely regulate the diversion of cargo to LROs. The research addresses the function of one of these, GLO-3, which is proposed to redirect the function of CCZ-1, a RAB-7 guanine nucleotide exchange factor (GEF), away from conventional endolysosomal pathways, toward the GLO-1 Rab to regulate LRO biogenesis. The research will involve detailed phenotypic analysis of mutants, yeast 2-hybrid screens, and in vitro GEF assays. The research will examine whether expressing GLO-3 and other LRO biogenesis factors are sufficient to direct the trafficking of LRO cargo away from conventional endosomes in cell types that do not normally generate LROs. The research will employ a novel genetic resource to identify nearly all of the genes necessary for LRO biogenesis in C. elegans.