Proteintargeting靶向蛋白范本.doc

Protein targeting From Wikipedia, the free encyclopedia This article deals with protein targeting in?eukaryotes?except where noted. Protein targeting?or?protein sorting?is the biological mechanism by which?proteins?are transported to the appropriate destinations in the cell or outside of it. Proteins can be targeted to the inner space of an?organelle, different intracellular?membranes,?plasma membrane, or to exterior of the cell via secretion. This delivery process is carried out based on information contained in the protein itself. Correct sorting is crucial for the cell; errors can lead to diseases. 靶向蛋白 维基百科，自由的百科全书 这篇文章除了注意的地方在真核生物蛋白靶向交易。 蛋白靶向或蛋白质排序是通过该蛋白质运输到细胞中的相应的目的地或它的外部的生物机制。蛋白质可靶向至细胞器，不同细胞内膜，质膜的内部空间，或通过分泌细胞的外部。这个输送过程是基于包含在该蛋白质本身的信息进行的。正确的排序是细胞的关键;错误可以导致疾病的发生。 Targeting signals Targeting signals are the pieces of information that enable the cellular transport machinery to correctly position a protein inside or outside the cell. This information is contained in the?polypeptide chain?or in the folded protein. The continuous stretch of?amino acid?residues in the chain that enables targeting are called?signal peptides?or?targeting peptides. There are two types of targeting peptides, the presequences and the internal targeting peptides. The presequences of the targeting peptide are often found at the N-terminal extension and is composed of between 6-136 basic and hydrophobic amino acids. In case of peroxisomes the targeting sequence is on the C-terminal extension mostly. Other signals, known as signal patches, are composed of parts which are separate in the?primary sequence. They become functional when?folding?brings them together on the protein surface. In addition,?protein modifications?like glycosylations can induce targeting. 靶向信号 定位信号是使蜂窝运输机械正确定位内或细胞外的蛋白质的信息块。此信息包含在该多肽链，或在折叠的蛋白质。的链中的氨基酸残基使得能够针对连续拉伸称为信号肽或靶向肽。有两种类型的靶向肽的前序列和内部靶向肽。所述靶向肽的前序列常常发现在N-端延伸，并6-136基本和疏水氨基酸之间组成。在过氧化物酶的情况下，靶向序列是在C-末端延伸居多。其他信号，称为信号贴剂，是由它们在一级序列分开的零件。当折叠使他们在一起蛋白质表面上他们变得功能。此外，像糖基化蛋白修饰可诱发靶向。 P