Biological roles of lectins in innate immunity: molecular and structural basis for diversity in self/non-self recognition.
Biological roles of lectins in innate immunity: molecular and structural basis for diversity in self/non-self recognition.
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DOI：
10.1007/978-0-387-71767-8_27
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发表时间：
2007
影响因子：
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通讯作者：
G. Vasta;H. Ahmed;Satoshi Tasumi;E. W. Odom;Keiko Saito
中科院分区：
文献类型：
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作者：
G. Vasta;H. Ahmed;Satoshi Tasumi;E. W. Odom;Keiko Saito
凝集素和其他模式识别蛋白是无脊椎动物和脊椎动物先天免疫机制的重要组成部分。与免疫球蛋白、TCR和VLR不同，它们通过基因重组产生识别多样性，凝集素像大多数先天免疫受体一样在种系中是“硬连线”的。因此，一个突出的问题是先天免疫系统如何能够科普潜在的微生物感染挑战的巨大多样性。虽然模式识别的概念提出，只有少数微生物保守的表面分子需要被识别成功的先天免疫防御，高度多样化的微生物群落，所有生物体暴露于和表面表达组分的动态变化表明，非自我识别机制的实质性多样性可能需要免疫保护。凝集素配体结合的结构基础的详细分析和缺乏适应性免疫的类群，如无脊椎动物的凝集素库的多样性和复杂性，强烈表明，这是这种情况。此外，最近的研究已经将这些观察结果扩展到变温脊椎动物。在这篇综述中，我们专注于识别和效应器功能的多样性程度仍然是实现。多基因家族、串联排列的多态性识别结构域、通过外显子改组形成嵌合结构以及它们的碳水化合物结合位点的相当大的“可塑性”的存在进一步有助于扩大凝集素作为先天免疫受体的配体识别谱和功能多样化。凝集素表达谱的时空变化进一步增强了这些受体在感染性攻击过程中的功能能力。此外，在进化过程中，C-凝集素和F-凝集素家族的一些成员已经被
Lectins and other pattern recognition proteins are critical components of innate immune mechanisms in invertebrates and vertebrates. Unlike immunoglobulins, TCRs, and VLRs, which generate diversity in recognition by genetic recombination, lectins like most innate immune receptors are “hard-wired” in the germline. Therefore, one of the outstanding questions is how the innate immune system is able to cope with the great diversity of potential microbial infectious challenges. Although the concept of pattern recognition proposes that only a handful of microbial conserved surface molecules need to be recognized for successful innate immune defense, the highly diversified microbial communities to which all organisms are exposed to and the dynamic changes in surface expression components suggests that a substantial diversity in non-self recognition mechanisms may be required for immune protection. The detailed analysis of the structural basis of lectin ligand binding and the diversity and complexity of the lectin repertoires in taxa that lack adaptive immunity, such as invertebrates, strongly suggests that this is the case. Further, recent studies have extended these observations to ectothermic vertebrates. In this review we focus on substantial degree of diversity in recognition and effector functions is still achieved. The presence of multigene families, tandemly arrayed polymorphic recognition domains, formation of chimeric structures by exon shuffling, and a considerable “plasticity” of their carbohydrate binding sites further contribute to expand the ligand recognition spectrum and functional diversification of lectins as innate immune receptors. Spatial and temporal changes in expression profiles of lectins further enhance the functional capacity of these receptors during infectious challenge. Further, in the course of evolution some members of both C-and F-lectin families have been