Evolution and arrangement of the hsp70 gene cluster in two closely related species of the virilis group of Drosophila
Evolution and arrangement of the hsp70 gene cluster in two closely related species of the virilis group of Drosophila
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DOI：
10.1007/s00412-004-0312-6
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发表时间：
2004-11-01
期刊：
影响因子：
1.6
通讯作者：
Feder, ME
中科院分区：
文献类型：
--
作者：
Evgen'ev, MB;Zatsepina, OG;Feder, ME
为了研究近缘果蝇和鲁美果蝇耐热性不同的遗传基础，我们研究了这两个物种的多个品系的HSP70基因簇。在这两个物种中，所有的HSP70拷贝都聚集在一个单一的染色体位点29c1上，每个簇包括两个以倒置对排列的HSP70基因，这是祖先的情况。耐热性较强的金黄色葡萄球菌的HSP70拷贝总数最多为7个，耐热性较差的金黄色葡萄球菌最多为5个，每个物种的某些菌株的拷贝数较低。因此，HSP70的最大拷贝数对应于先前报道的HSP70 mRNA和HSP70蛋白水平以及29c1处热诱导泡腾的大小。HSP70拷贝的核苷酸序列和间距与维氏原虫和鲁美原虫的共同祖先中HSP70基因的串联重复以及鲁美原虫HSP70基因的缺失是一致的。这些和其他关于果蝇HSP70的数据表明，进化适应通过几种不同的遗传机制反复修改了HSP70的拷贝数。
To investigate the genetic basis of differing thermotolerance in the closely related species Drosophila virilis and Drosophila lummei, which replace one another along a latitudinal cline, we characterized the hsp70 gene cluster in multiple strains of both species. In both species, all hsp70 copies cluster in a single chromosomal locus, 29C1, and each cluster includes two hsp70 genes arranged as an inverted pair, the ancestral condition. The total number of hsp70 copies is maximally seven in the more thermotolerant D. virilis and five in the less tolerant D. lummei, with some strains of each species exhibiting lower copy numbers. Thus, maximum hsp70 copy number corresponds to hsp70 mRNA and Hsp70 protein levels reported previously and the size of heat-induced puffs at 29C1. The nucleotide sequence and spacing of the hsp70 copies are consistent with tandem duplication of the hsp70 genes in a common ancestor of D. virilis and D. lummei followed by loss of hsp70 genes in D. lummei. These and other data for hsp70 in Drosophila suggest that evolutionary adaptation has repeatedly modified hsp70 copy number by several different genetic mechanisms.