Intracellular Sorting and Translocation of Proteins into Plant Peroxisomes

9604501 T释放技术细胞内代谢途径的区隔是真核细胞内调节机制的一个主要方面。适当的细胞内分选和将蛋白质转移到正确的细胞器中是亚细胞分隔的基本组成部分。过氧化物酶体执行一系列不同的代谢功能，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从实验上确定植物细胞中的乙氧基体(一种特殊类型的过氧酶体)从细胞质中合成部位获得蛋白质的方式。实验将使用特性良好的体内蛋白质输入系统，即悬浮培养烟草BY-2细胞。目标1是确定嵌合体蛋白通过PTS1途径正确分选为BY-2乙氧基体所需的氨基酸残基的C-末端位置和变异。目的2阐明氨基酸残基在通过pts2途径将蛋白质分类为乙氧基体的N端纳米肽中的位置和变化。与这些目标相一致，将开始研究鉴定和表征与蛋白质通过植物乙氧基体边界膜转运有关的假定的膜蛋白。非技术性植物细胞含有一种被称为过氧化体的细胞内细胞器，该细胞器在糖和脂肪酸的新陈代谢中发挥作用。过氧化酶体是如何组装的一直是细胞生物学中的一个重大争议。蛋白质如何被导向各种亚细胞隔间的机制是通过靶向作为蛋白质固有部分的序列来实现的。特雷利斯博士将进行研究，以确定将目标蛋白质整合到过氧酶体所需的准确序列。***

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. ***