Wolf P R, Cook R G
Department of Microbiology and Immunology, Baylor College of Medicine, Houston, Texas 77030.
J Exp Med. 1990 Dec 1;172(6):1795-804. doi: 10.1084/jem.172.6.1795.
Of all the biochemically defined mouse MHC class I molecules, the Qa-1 antigens are the only ones for which a gene has not been identified. Recent evidence has suggested that Qa-1 antigens are functional class I molecules and can function as restriction elements for gamma/delta T cells. We have examined the relationship between Qa-1 and the product of gene 37, a presumed novel class I antigen encoded within the TL region. Immunoprecipitation and polyacrylamide gel electrophoresis analysis of the molecules reactive with anti-Qa-1 and anti-37 sera show that the Qa-1 molecule of Qa-1b (Qa-1.2) mouse strains is identical to the product of gene 37 on the basis of molecular weight, pI, and strain distribution. Immunodepletion, biosynthetic labeling, and tunicamycin treatment confirm that the protein encoded by gene 37 in Qa-1b mice is Qa-1.2. In contrast, the anti-37 serum was unable to recognize the Qa-1 molecule in Qa-1a strains. Given the fact that the only allele to gene 37 thus far identified in a Qa-1a strain (A/J) has a termination codon in the alpha 3 domain, our data lead us to conclude that the Qa-1 molecule expressed in Qa-1a mice is not a true allelic product of the gene 37 encoded antigen of Qa-1b mouse strains.
在所有经过生物化学定义的小鼠MHC I类分子中，Qa-1抗原是唯一尚未鉴定出相关基因的分子。最近的证据表明，Qa-1抗原是功能性I类分子，可作为γ/δ T细胞的限制元件。我们研究了Qa-1与基因37产物之间的关系，基因37是位于TL区域内的一种推测的新型I类抗原。用抗Qa-1和抗37血清对反应性分子进行免疫沉淀和聚丙烯酰胺凝胶电泳分析表明，基于分子量、pI和品系分布，Qa-1b（Qa-1.2）小鼠品系的Qa-1分子与基因37的产物相同。免疫去除、生物合成标记和衣霉素处理证实，Qa-1b小鼠中基因37编码的蛋白是Qa-1.2。相反，抗37血清无法识别Qa-1a品系中的Qa-1分子。鉴于到目前为止在Qa-1a品系（A/J）中鉴定出的基因37的唯一等位基因在α3结构域中有一个终止密码子，我们的数据使我们得出结论，Qa-1a小鼠中表达的Qa-1分子不是Qa-1b小鼠品系中基因37编码抗原的真正等位基因产物。
