IDENTIFICATION AND SYNTHESIS OF A RECOGNITION SIGNAL FOR THE ATTACHMENT OF GLYCOSAMINOGLYCANS TO PROTEINS
IDENTIFICATION AND SYNTHESIS OF A RECOGNITION SIGNAL FOR THE ATTACHMENT OF GLYCOSAMINOGLYCANS TO PROTEINS
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DOI：
10.1073/pnas.84.10.3194
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发表时间：
1987-05-01
影响因子：
11.1
通讯作者：
RUOSLAHTI, E
中科院分区：
文献类型：
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作者：
BOURDON, MA;KRUSIUS, T;RUOSLAHTI, E
比较三种不同蛋白多糖核心蛋白的氨基酸序列揭示了这些蛋白多糖之间大约有 50% 同源性的 12 个氨基酸序列。在每种蛋白聚糖中，该序列围绕丝氨酸-甘氨酸二肽，其中已知或推测丝氨酸被软骨素/硫酸皮肤素糖胺聚糖链取代。检查了含有来自两种蛋白聚糖的该序列的肽作为木糖基转移酶受体的能力，木糖基转移酶是开始糖胺聚糖链组装的酶。对应于已知在蛋白质中含有糖胺聚糖取代的丝氨酸残基的氨基酸序列的那些肽是有效的木糖基转移酶受体，而来自不含糖胺聚糖取代的丝氨酸残基的序列的肽则不是。受体肽中四个关键位点的氨基酸取代表明，单一取代可以完全消除受体活性或大大降低受体活性。结果表明，将糖胺聚糖附着到核心蛋白上的蛋白聚糖识别共有序列由酸性氨基酸组成，紧随其后的是四肽 Ser-Gly-Xaa-Gly，其中 Xaa 是氨基酸。该信号似乎包含在初级序列信息中。在这方面，它类似于蛋白质加工和细胞内路由的许多其他信号。
Comparison of the amino acid sequences of three different proteoglycan core proteins reveals a 12-amino acid sequence that is about 50% homologous among these proteoglycans. In each of the proteoglycans, this sequence surrounds the serine-glycine dipeptide in which the serine is known or presumed to be substituted with a chondroitin/dermatan sulfate glycosaminoglycan chain. Peptides containing this sequence from two proteoglycans were examined for their ability to serve as acceptors for xylosyltransferase, the enzyme that begins the assembly of glycosaminoglycan chains. Those peptides corresponding to amino acid sequences known to contain glycosaminoglycan-substituted serine residues in the protein were efficient xylosyltransferase acceptors, whereas peptides from sequences with no glycosaminoglycan-substituted serine residues were not. Amino acid substitutions at four critical sites in the acceptor peptides showed that single substitutions could completely abolish acceptor activity or greatly reduce it. The results suggest that the proteoglycan recognition consensus sequence for the attachment of glycosaminoglycans to core proteins consists of acidic amino acids closely followed by the tetrapeptide Ser-Gly-Xaa-Gly, where Xaa is an amino acid. The signal appears to be contained in the primary sequence information. In this regard it resembles a number of other signals for protein processing and intracellular routing.