Hsp70 duplication in the Drosophila melanogaster species group:: How and when did two become five?
Hsp70 duplication in the Drosophila melanogaster species group:: How and when did two become five?
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DOI：
10.1093/oxfordjournals.molbev.a003912
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发表时间：
2001-07-01
影响因子：
10.7
通讯作者：
Feder, ME
中科院分区：
文献类型：
--
作者：
Bettencourt, BR;Feder, ME
为了确定黑腹果蝇中hsp 70基因的现代拷贝数（5）是如何进化的，我们定位了黑腹果蝇群体中产生该基因的复制事件，检测了D.黑腹果蝇基因组序列的同源性分析，探讨其复制机制，并对果蝇和毛里求斯果蝇的hsp 70基因序列进行了分析。最初的两到四个hsp 70重复发生10-15 MYA，根据固定的多线染色体原位杂交，在黑腹鱼和五个其他物种亚群的起源和分歧之前，黑腹鱼组。对hsp 70基因簇周围超过30 kb的侧翼序列的分析表明，这种重复可能是一种反转录转座。Southern杂交和hsp 70酶切图谱证实了黑腹果蝇亚群中除果蝇外的7种果蝇hsp 70基因的保守数目和排列方式。黑腹菌黑腹果蝇是独一无二的，在衍生簇中的串联重复和基因转换产生了第五个hsp 70基因。四个D orena热休克蛋白70基因是高度相似和协调进化的。与此相反，D.毛里求斯hsp 70基因具有多样性，且等位基因较多。是不起作用的。在D.黑腹果蝇hsp 70基因与该物种的自然选择作用相一致。
To determine how the modem copy number (5) of hsp70 genes in Drosophila melanogaster evolved, we localized the duplication events that created the genes in the phylogeny of the melanogaster group, examined D. melanogaster genomic sequence to investigate the mechanisms of duplication, and analyzed the hsp70 gene sequences of Drosophila orena and Drosophila mauritiana. The initial two-to-four hsp70 duplication occurred 10-15 MYA, according to fixed in situ hybridization to polytene chromosomes, before the origin and divergence of the melanogaster and five: other species subgroups of the, melanogaster group. Analysis of more than 30 kb of flanking sequence surrounding the hsp70 gene clusters suggested that this duplication was Likely a retrotransposition. For the melanogaster subgroup, Southern hybridization and an hsp70 restriction map confirmed the conserved number (4) and arrangement of hsp70 genes in the seven species other than D. melanogaster. Drosophila melanogaster is unique; tandem duplication and gene conversion at the derived cluster yielded a fifth hsp70 gene. The four D. orena hsp70 genes are highly similar and concertedly evolving. In contrast, the D. mauritiana hsp70 genes are divergent, and many alleles. are nonfunctional. The proliferation, concerted evolution, and maintenance of functionality in the D. melanogaster hsp70 genes is consistent with the, action of natural selection in this species.