PGRL is a major CD81-associated protein on lymphocytes and distinguishes a new family of cell surface proteins
PGRL is a major CD81-associated protein on lymphocytes and distinguishes a new family of cell surface proteins
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DOI：
10.4049/jimmunol.167.9.5115
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发表时间：
2001-11-01
影响因子：
4.4
通讯作者：
Todd, SC
中科院分区：
文献类型：
--
作者：
Clark, KL;Zeng, ZH;Todd, SC
CD81在T细胞上发挥一系列有趣的作用，包括胸腺细胞早期分化、LFA-1激活和提供共刺激。为了更好地了解CD81影响T细胞功能的机制，我们研究了CD81分子复合体对T细胞的影响。胸腺细胞以及一些T细胞和B细胞系上最显著的CD81相关细胞表面蛋白的表观分子质量为75 kDa。用基质辅助激光解吸电离飞行时间质谱仪对75 kDa的蛋白质进行纯化和分析，然后进行源后衰变分析。P75是免疫球蛋白超家族的一种新的I型跨膜蛋白，与FPRP最为相似。我们克隆和测序了人和小鼠PG调节样蛋白(PGRL)，并研究了小鼠PGRL在淋巴细胞和非淋巴组织中的表达。PGRL的发现使包括PGRL、FPRP、V7/CD101和IGSF3在内的相关蛋白小家族得以聚集。含有带有表位标签的PGRL不同结构域的表达载体与CD81共表达，并用于确定CD81与PGRL的相互作用需要PGRL的膜远端1G3-1G4结构域。尽管PGRL是否具有PG调节功能尚不清楚，但Transwell小室实验表明，PGs和CD81协同调节T细胞的运动。
CD81 exerts a range of interesting effects on T cells including early thymocyte differentiation, LFA-1 activation, and provision of costimulation. To better understand the mechanisms by which CD81 influences T cell function we evaluated CD81 molecular complexes on T cells. The most prominent CD81-associated cell surface protein on thymocytes as well as a number of T cell and B cell lines has an apparent molecular mass of 75 kDa. The 75-kDa protein was purified and analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry followed by postsource-decay profiling. p75 is a novel type I transmembrane protein of the Ig superfamily which is most similar to FPRP. We cloned and sequenced both human and mouse PG regulatory-like protein (PGRL) and characterized mouse PGRL expression in both lymphocytes and nonlymphoid tissues. The discovery of PGRL allows for the clustering of a small family of related proteins including PGRL, FPRP, V7/CD101, and IGSF3. Expression constructs containing various domains of PGRL with an epitope tag were coexpressed with CD81 and used to determine that the interaction of CD81 with PGRL requires the membrane distal 1g3-1g4 domains of PGRL. Although it remains to be determined whether PGRL possesses PG regulatory functions, transwell chamber experiments show that PGs and CD81 coordinately regulate T cell motility.