Yazaki A, Ohno S
Proc Natl Acad Sci U S A. 1983 Apr;80(8):2337-40. doi: 10.1073/pnas.80.8.2337.
Within the published 2,168-base-long mouse C mu gene of Ig heavy chain consisting of four coding and four noncoding segments, 2 base decamers, 8 nonomers, and 39 octamers recurred. Recurring base heptamers (about 100) and hexamers (about 350) were simply too numerous to merit individual identification. In spite of extensive overlaps between these recurring base decamers to hexamers, they occupied nearly the entire length of mouse Ig C mu gene. As with other genes of the beta-sheet-forming beta 2-microglobulin family, the Ig C mu gene (flanking and intervening noncoding sequences included) is not a unique sequence but rather it is degenerate repeats of the 45-base-long primordial building-block sequence uniquely its own. This primordial building block must originally have specified the 15-amino-acid-residue-long primordial arm of beta-sheet-forming loops, the characteristics of the beta 2-microglobulin family of polypeptides.
在已发表的由四个编码和四个非编码区段组成的2168个碱基长的小鼠免疫球蛋白重链Cμ基因中，出现了2个碱基十聚体、8个碱基九聚体和39个碱基八聚体。反复出现的碱基七聚体（约100个）和六聚体（约350个）数量太多，无法逐一识别。尽管这些反复出现的碱基十聚体到六聚体之间有广泛重叠，但它们几乎占据了小鼠免疫球蛋白Cμ基因的全长。与形成β折叠的β2微球蛋白家族的其他基因一样，免疫球蛋白Cμ基因（包括侧翼和间隔的非编码序列）不是一个独特的序列，而是由其特有的45个碱基长的原始构建块序列的简并重复组成。这个原始构建块最初一定指定了形成β折叠环的15个氨基酸残基长的原始臂，这是β2微球蛋白家族多肽的特征。
