秀丽隐杆线虫抗铜突变体的筛选及SNP定位  

Screening and SNP mapping of copper-resistant mutations in C. elegans

作　　者：宋少娟[1] 郭亚平[2] 张学尧[1] 张建珍[1] 马恩波[1] 

机构地区：[1]山西大学应用生物研究所,太原030006 [2]山西大学生命科学学院,太原030006

出　　处：《遗传》2014年第12期1261-1268,共8页Hereditas（Beijing)

基　　金：国家自然科学基金项目(编号:31071980)资助

摘　　要：铜在有机体代谢过程中发挥着重要作用,但过量可产生毒害效应。文章以秀丽隐杆线虫(Caenorhabditis elegans)为模式生物,寻找多细胞生物中铜代谢调节的关键基因。采用甲基磺酸乙酯(EMS)诱变秀丽隐杆线虫,通过100 000个杂合基因组的筛选得到两个抗铜突变体ms1和ms2。在筛选培养基上野生型停止发育,而抗铜突变体则可发育到成虫,且抗铜性状能稳定遗传。与N2的回交实验表明,ms1的抗铜表型可能由单基因隐性突变导致,ms2的抗铜表型消失,可能是由多基因突变引起。以CB4856和ms1作为亲本,构建了F2群,经SNP定位,确定ms1突变位点位于染色体II(LGII)上,进一步对LGII染色体上的8个SNP标记进行分析,将ms1的突变位点定位在LGII:-6附近。秀丽隐杆线虫抗铜突变体ms1的筛选和定位可为深入研究线虫铜代谢及调控的分子机制提供实验依据。Copper plays critical roles in biological system; however, it is toxic in excess. To identify novel genes involved in copper metabolism, we performed a whole genome-wide genetic screen in C. elegans model organism to search for mutants which are resistant to excessive copper. Wild type （N2） L4 worms were mutagenized with ethyl-methane sulfonate （EMS）, and the F2 progeny were screened on culture medium with excess copper. Two cop-per-resistant mutants, ms1 and ms2, were recovered from the screening of 100 000 hyploid genomes. No obvious developmental defects were observed in ms1 and ms2 mutants, and they were able to grow into adults on screen me-dium plate, but N2 worms arrested in L1 stage. Results of backcross test suggested that copper-resistant phenotype in ms1 may be controlled by a single recessive gene, but probably there are mutations in multiple genes in ms2, as no copper resistant worms could be found in F2 progeny when ms2 mutants were backcrossed with N2 worms. To determine the mutation positions of ms1, we employed single nucleotide polymorphisms （SNPs） mapping. Our mapping results indicated that ms1 mutation is on chromosome II （LGII）. By analysis of 8 SNP markers from-18 to 23 on LGII, we found that ms1 mutation is at approximately LGII：-6. Further study on ms1 mutants will provide insights into copper metabolism and its regulation.

关 键 词：秀丽隐杆线虫 正向遗传筛选 抗铜 突变体 SNP定位 

分 类 号：Q78[生物学—分子生物学]