Thiele C J, Owens J D, Finkelman F D, Mushinski J F
J Immunol. 1985 Feb;134(2):1251-6.
An unusually small (51 KD) IgD myeloma protein was isolated from secretions of TEPC 1017 generation (gen) 24. The delta-chain mRNA and the delta-chain gene in this tumor were compared with those of TEPC 1017 of earlier generations. The gen 24 protein contained one normal-sized kappa-type light chain (21 KD) and one unusually short delta-heavy chain (30 KD). The delta-heavy chain was 15 KD shorter than that of TEPC 1017 of earlier generations, owing to a delta-mRNA (1.15 kb) which was 600 bp shorter than that of TEPC 1017 of earlier generations. TEPC 1017 is a tetraploid tumor, and the gen 24 appears to contain at least two different deletions on different chromosomes. The short mRNA was produced from one of these altered delta-chain genes which had a productive VDJ rearrangement but which had lost the C delta 3 domain and perhaps the C delta H domain as well. Despite these genetic insults, RNA splicing produced delta-mRNA with secreted termini and mRNA with membrane-binding termini. It is suggested that the mouse C delta gene has an unusual predilection for deletions because it normally lacks any vestige of C delta 2 and, during i.p. passage, it suffered further deletions or alterations.
从TEPC 1017第24代（gen）的分泌物中分离出一种异常小（51 KD）的IgD骨髓瘤蛋白。将该肿瘤中的δ链mRNA和δ链基因与早期TEPC 1017的进行比较。第24代蛋白包含一条正常大小的κ型轻链（21 KD）和一条异常短的δ重链（30 KD）。δ重链比早期TEPC 1017的重链短15 KD，这是由于δ - mRNA（1.15 kb）比早期TEPC 1017的短600 bp。TEPC 1017是一种四倍体肿瘤，第24代似乎在不同染色体上至少有两个不同的缺失。短mRNA由这些改变的δ链基因之一产生，该基因具有有效的VDJ重排，但失去了Cδ3结构域，可能还失去了CδH结构域。尽管有这些基因损伤，但RNA剪接产生了具有分泌末端的δ - mRNA和具有膜结合末端的mRNA。有人提出，小鼠Cδ基因对缺失有异常的偏好，因为它通常缺乏Cδ2的任何痕迹，并且在腹腔传代过程中，它遭受了进一步的缺失或改变。
