Baksa K, Morawietz H, Dombrádi V, Axton M, Taubert H, Szabó G, Török I, Udvardy A, Gyurkovics H, Szöör B
Institute of Biochemistry, Biological Research Centre, Szeged, Hungary.
Genetics. 1993 Sep;135(1):117-25. doi: 10.1093/genetics/135.1.117.
The suppressor of position effect variegation (PEV) locus Su-var(3)6 maps to 87B5-10. The breakpoints of deficiencies that define this interval have been placed on a 250-kb molecular map of the region. The locus is allelic to the ck19 complementation group previously shown to encode a type 1 serine-threonine protein phosphatase (PP1) catalytic subunit. When introduced into flies by P element-mediated transformation, a 5.8-kb genomic fragment carrying this gene overcomes the suppressor phenotype of Su-var(3)6(01) and recessive lethality of all mutations of the locus. Four of the mutant alleles at the locus show a broad correlation between high levels of suppression of PEV, a high frequency of aberrant mitosis and low PP1 activity in larval extracts. However, some alleles with low PP1 activity show weak suppression of PEV with a high frequency of abnormal mitosis, whereas others show strong suppression of PEV with normal mitosis. The basis for these discussed.
位置效应斑驳(PEV)抑制基因座Su-var(3)6定位于87B5-10。定义该区间的缺失断点已定位在该区域的250 kb分子图谱上。该基因座与先前显示编码1型丝氨酸-苏氨酸蛋白磷酸酶(PP1)催化亚基的ck19互补群等位。当通过P因子介导的转化导入果蝇时,携带该基因的5.8 kb基因组片段克服了Su-var(3)6(01)的抑制表型和该基因座所有突变的隐性致死性。该基因座的四个突变等位基因显示出高水平的PEV抑制、高频率的异常有丝分裂与幼虫提取物中低PP1活性之间的广泛相关性。然而,一些具有低PP1活性的等位基因显示出对PEV的弱抑制以及高频率的异常有丝分裂,而其他等位基因则显示出对PEV的强抑制以及正常的有丝分裂。文中对这些情况的依据进行了讨论。