Duplication of primate and rodent B7-H3 immunoglobulin V- and C-like domains: divergent history of functional redundancy and exon loss

被引：151

作者：

Ling, V ^{[1
]}

Wu, PW ^{[1
]}

Spaulding, V ^{[1
]}

Kieleczawa, J ^{[1
]}

Luxenberg, D ^{[1
]}

Carreno, BM ^{[1
]}

Collins, M ^{[1
]}

机构：

[1] Wyeth Ayerst Res, Cambridge, MA 02140 USA

来源：

GENOMICS | 2003年 / 82卷 / 03期

关键词：

B7; costimulation; immune modulation; immunoglobulin variable domain;

D O I：

10.1016/S0888-7543(03)00126-5

中图分类号：

Q81 [生物工程学（生物技术）]; Q93 [微生物学];

学科分类号：

071005 ; 0836 ; 090102 ; 100705 ;

摘要：

B7-H3 is a novel protein structurally related to the B7 family of ligands by the presence of a single set of immunoglobulin-V-Iike and immunoglobulin-C-like (VC) domains. By multiplex PCR, the dominantly expressed form of human B7-H3 was found to be a splice variant containing tandemly duplicated VC domains (VCVC). In contrast, mouse B7-H3 cDNA contained only one single VC form due to an exon structure corresponding to V-(pseudoexon C)-(pseudoexon V)-C. Comparisons of human, monkey, mouse, and hamster genomic B7-H3 reveal that primates, but not rodents, exhibited a higher degree of intramolecular sequence similarity between VC duplications than between molecules. Both VC and VCVC forms of human B7-H3 inhibited CD4(+) T cell proliferation and downregulated cytokine production upon TCR activation. These results suggest independent, but convergent, paths of B7-H3 active domain duplication followed by divergent histories of exon degeneration in rodents and exon maintenance by humans. (C) 2003 Elsevier Science (USA). All rights reserved.

引用

页码：365 / 377

页数：13

共 33 条

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