L-5178Y TK+/TK-小鼠淋巴瘤细胞系中APRT基因座突变体的分离与鉴定。

Isolation and characterization of mutants at the APRT locus in the L-5178Y TK+/TK- mouse lymphoma cell line.

作者信息

Paeratakul U, Taylor M W

出版信息

Mutat Res. 1986 Mar;160(1):61-9. doi: 10.1016/s0027-5107(96)90010-x.

Abstract

2,6-Diaminopurine(DAP)-resistant mutants have been isolated from mouse lymphoma 5178Y TK+/TK- heterozygotes. In the presence of 50 microM DAP, two colony types were isolated. Small colonies contained 50% wild-type adenine phosphoribosyl transferase (APRT) activity (partial mutants), whereas large colonies have undetectable levels of APRT (aprt- mutants). aprt- mutants could be isolated following mutagenesis with ICR-191 or EMS from the partial mutants. Southern blot analysis of EcoRI digested wild-type DNA using a 3.1 kb mouse aprt genomic probe indicated sequence polymorphism at one or both EcoRI sites flanking the allele. Southern blot analysis of one of the partial mutants and one ICR-induced aprt- mutant (single step) indicated that both strains were hemizygous at the APRT locus. Such stable hemizygous strains would be useful in short-term mutagen tests.

摘要

已从小鼠淋巴瘤5178Y TK+/TK-杂合子中分离出对2,6-二氨基嘌呤（DAP）具有抗性的突变体。在存在50微摩尔DAP的情况下，分离出了两种菌落类型。小菌落含有50%的野生型腺嘌呤磷酸核糖转移酶（APRT）活性（部分突变体），而大菌落的APRT水平检测不到（aprt-突变体）。aprt-突变体可通过用ICR-191或EMS对部分突变体进行诱变后分离得到。使用3.1 kb小鼠aprt基因组探针对经EcoRI消化的野生型DNA进行Southern印迹分析，结果表明等位基因两侧的一个或两个EcoRI位点存在序列多态性。对其中一个部分突变体和一个ICR诱导的aprt-突变体（单步）进行Southern印迹分析表明，这两个菌株在APRT基因座均为半合子。这种稳定的半合子菌株在短期诱变试验中会很有用。