Intracellular Sorting and Translocation of Proteins into Plant Peroxisomes

小行星9604501 细胞器内代谢途径的区室化是真核细胞内调控机制的一个主要方面。正确的细胞内分选和蛋白质易位到正确的细胞器是亚细胞区室化的基本组成部分。过氧化物酶体进行多种多样的代谢功能，这取决于它们所在的细胞或组织类型。这项研究的总体目标是通过实验确定植物细胞中的乙醛酸酶体（一种特殊类型的过氧化物酶体）从细胞质中的合成位点获得蛋白质的方法。实验将用充分表征的体内蛋白质输入系统，即悬浮培养的烟草BY-2细胞进行。目的1将是确定C-末端定位和氨基酸残基的变化，这是足够的适当的分选嵌合蛋白BY-2通过PTS 1途径的乙醛酸酶体。目的2将阐明N-末端纳米肽内氨基酸残基的定位和变化，该纳米肽通过PTS 2途径将蛋白质分选为乙醛酸酶体。与这些目标相一致，研究将启动，以确定和表征推定的膜蛋白参与易位的蛋白质通过边界膜的植物乙醛酸酶体。 非技术植物细胞含有一种称为过氧化物酶体的细胞内细胞器，其在糖和脂肪酸的代谢中起作用。过氧化物酶体是如何组装的一直是细胞生物学中的一个主要争议。蛋白质如何被定向到各种亚细胞区室的机制是通过作为蛋白质内在部分的靶向序列。Trelease博士将进行研究，以确定将目标蛋白质纳入过氧化物酶体所需的确切序列。 ***

9604501 Trelease Technical Compartmentation of metabolic pathways within cellular organelles is a major aspect of the regulatory mechanisms that operate within eukaryotic cells. Proper intracellular sorting and translocation of proteins into the correct organelle are essential components of subcellular compartmentation. Peroxisomes conduct a diverse array of metabolic functions which depend on the cell or tissue type in which they reside. The overall goal of the research is to experimentally define the means by which glyoxysomes (a specialized type of peroxisome) in plant cells acquire proteins from their site of synthesis in the cytosol. Experiments will be done with the well-characterized in-vivo protein import system, namely suspension-cultured tobacco BY-2 cells. Objective 1 will be to determine the C-terminal positioning and variation of amino acid residues which are sufficient for proper sorting of chimepic proteins to BY-2 glyoxysomes via the PTS1 pathway. Objective 2 will be to elucidate the positioning and variation of amino acid residues within a N-terminal nanopeptide which sorts proteins to glyoxysomes via the PTS2 pathway. In concert with these objectives, studies will be initiated to identify and characterize putative membrane proteins involved in translocation of proteins through the boundary membrane of plant glyoxysomes. Non-technical Plant cells contain an intracellular organelle termed peroxisome that functions in the metabolism of sugars and fatty acids. How the peroxisome is assembled has been a major controversy in cell biology. The mechanism of how proteins are directed to various subcellular compartments is through targeting sequences that are an intrinsic part of the protein. Dr. Trelease will conduct research to determine the exact sequences necessary to target proteins to be incorporated into peroxisomes. ***