Gavin A L, Leiter E H, Hogarth P M
Helen M. Schutt Laboratory for Immunology, The Austin Research Institute, The Austin and Repatriation Medical Centre, Heidelberg VIC, Australia.
Immunogenetics. 2000 Mar;51(3):206-11. doi: 10.1007/s002510050033.
The mouse Fcgr1 gene encoding the high-affinity IgG receptor (FcgammaRI) exists as two known alleles, FcgammaRI-BALB and FcgammaRI-NOD, and these alleles exhibit functional differences. To determine whether other alleles exist in mouse strains, Fcgr1 coding regions from 35 strains of mice were sequenced and a further five alleles were identified. The FcgammaRI-BALB and NOD alleles are now designated the "a" and "d" alleles, respectively. Analysis of the five new alleles revealed that although no polymorphisms were observed in the two leader exons, nucleotide and subsequent amino acid changes were observed in the exons encoding the extracellular domains, and transmembrane and cytoplasmic tail. The cDNA of the seven alleles (a-g) were isolated and transiently transfected into COS cells, and IgG-binding studies were performed. Receptors encoded by four of the five new alleles (b, c, f, g) bound IgG2a with high affinity, displaying IgG binding characteristics similar to the a allele (previously FcgammaRI-BALB). The d allele (previously FcgammaRI-NOD) and the e allele [derived from Mus spretus (SPRET/Ei)] encoded receptors which showed broader specificity by binding monomeric IgG2a, IgG2b, and IgG3.
编码高亲和力IgG受体（FcγRI）的小鼠Fcgr1基因以两种已知等位基因形式存在，即FcγRI - BALB和FcγRI - NOD，并且这些等位基因表现出功能差异。为了确定小鼠品系中是否存在其他等位基因，对35个小鼠品系的Fcgr1编码区进行了测序，并鉴定出另外五个等位基因。FcγRI - BALB和NOD等位基因现在分别被指定为“a”和“d”等位基因。对这五个新等位基因的分析表明，尽管在两个前导外显子中未观察到多态性，但在编码细胞外结构域、跨膜结构域和细胞质尾的外显子中观察到了核苷酸及随后的氨基酸变化。分离出七个等位基因（a - g）的cDNA并将其瞬时转染到COS细胞中，然后进行IgG结合研究。五个新等位基因中的四个（b、c、f、g）编码的受体与IgG2a具有高亲和力结合，显示出与a等位基因（先前的FcγRI - BALB）相似的IgG结合特性。d等位基因（先前的FcγRI - NOD）和e等位基因[源自小家鼠（SPRET/Ei）]编码的受体通过结合单体IgG2a、IgG2b和IgG3表现出更广泛的特异性。
