Heparan sulfate oligosaccharides require 6-O-sulfation for promotion of basic fibroblast growth factor mitogenic activity
Heparan sulfate oligosaccharides require 6-O-sulfation for promotion of basic fibroblast growth factor mitogenic activity
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DOI：
10.1074/jbc.273.36.22936
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发表时间：
1998-09-04
影响因子：
4.8
通讯作者：
Gallagher, JT
中科院分区：
文献类型：
--
作者：
Pye, DA;Vives, RR;Gallagher, JT
硫酸乙酰肝素 (HS) 与碱性成纤维细胞生长因子 (bFGF) 的相互作用对生长因子与其细胞表面酪氨酸激酶受体结合有影响。在本研究中，我们进一步研究了在促有丝分裂测定中介导 bFGF 活性所需的 HS 的结构特性。我们准备了一个肝素酶 m 生成的 HS 寡糖文库，按其大小 (dp6-dp12) 和硫酸盐含量进行分级。然后将这些寡糖在促有丝分裂测定中激活 bFGF 的能力与其长度和二糖组成相关联。所有测试的八糖和六糖级分均无法激活 bFGF。十二糖和十糖级分被发现含有活化和非活化寡糖，并且显示出总硫酸盐含量和活化活性水平之间存在明显的相关性。对一系列十二糖和十糖组分的二糖分析表明，活化和非活化寡糖主要由 N-硫酸化和含 IdoA(2S) 的二糖组成。活化寡糖和非活化寡糖之间的唯一显着差异是6-O-硫酸化二糖的含量，特别是二糖IdoA(2S)α 1,4GlcNSO(3)(6S)。这些结果表明，除了 IdoA 的 2-0-硫酸化之外，还需要 N-硫酸化葡萄糖胺残基的 B-O-硫酸化，以促进天然存在的 HS 寡糖的 bFGF 有丝分裂活性。特别是对十二糖级分中的结构-活性关系的分析表明，存在最小的 bFGF 激活序列，该序列取决于至少一个 6-O-硫酸酯基团的定位。
The interaction of heparan sulfate (HS) with basic fibroblast growth factor (bFGF) is influential in enabling the growth factor to bind to its cell surface tyrosine kinase receptor. In this study, we have investigated further the structural properties of HS required to mediate the activity of bFGF in a mitogenic assay. We have prepared a library of heparinase m-generated HS oligosaccharides fractionated by both their size (dp6-dp12) and sulfate content. The ability of these oligosaccharides to activate bFGF in a mitogenic assay was then correlated with their length and disaccharide composition. All octa- and hexasaccharide fractions tested were unable to activate bFGF. Dodeca- and decasaccharide fractions were found to contain both activating and nonactivating oligosaccharides, and showed a clear correlation between total sulfate content and the level of activatory activity. Disaccharide analysis of a range of dodeca- and decasaccharide fractions showed that both activating and non-activating oligosaccharides were composed mainly of N-sulfated and IdoA(2S)-containing disaccharides. The only significant difference between activating and non-activating oligosaccharides was the content of 6-O-sulfated disaccharides, in particular the disaccharide IdoA(2S)alpha 1,4GlcNSO(3)(6S). These results show that there is a requirement for B-O-sulfation of N-sulfated glucosamine residues, in addition to the 2-0-sulfation of IdoA, for the promotion of bFGF mitogenic activity by naturally occurring HS oligosaccharides. Analysis of the structure-activity relationships in the dodecasaccharide fractions in particular, suggests that a minimum bFGF activation sequence exists which is dependent on the positioning of at least one 6-O-sulfate group.