Transposable Elements Mediate Adaptive Debilitation of Flagella in Experimental Escherichia coli Populations.
Transposable Elements Mediate Adaptive Debilitation of Flagella in Experimental Escherichia coli Populations.
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DOI：
10.1007/s00239-017-9797-5
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发表时间：
2017-06
影响因子：
3.9
通讯作者：
Costa D
中科院分区：
文献类型：
--
作者：
Plague GR;Boodram KS;Dougherty KM;Bregg S;Gilbert DP;Bakshi H;Costa D
尽管插入序列（IS）元件通常被认为是基因组寄生物，但它们可以介导细菌基因组中的适应性遗传变化。我们发现，在12个实验室进化的大肠杆菌种群中，有三个经历了至少六种不同的IS1介导的鞭毛基因缺失。这些缺失均涉及主鞭毛调节因子flhDC，因此完全丧失运动性。两条证据有力地表明，这些缺失在我们的进化实验中是适应性的：（1）三个独立种群中的平行进化极不可能只是偶然的，（2）其中一个缺失突变在约1000代内被清除到固定，如果这个缺失是选择性中性的，那么通过遗传漂变进化，这比预期的要快200万倍。由于鞭毛的合成和运作都需要耗费大量的能量，我们怀疑削弱它们的结构会在我们搅拌良好的进化实验中带来适应性优势。这些发现强调了IS元件在介导细菌适应性功能丧失突变中的重要作用。
Although insertion sequence (IS) elements are generally considered genomic parasites, they can mediate adaptive genetic changes in bacterial genomes. We discovered that among 12 laboratory-evolved Escherichia coli populations, three had experienced at least six different IS1-mediated deletions of flagellar genes. These deletions all involved the master flagellar regulator flhDC, and as such completely incapacitate motility. Two lines of evidence strongly suggest that these deletions were adaptive in our evolution experiment: (1) parallel evolution in three independent populations is highly unlikely just by chance, and (2) one of these deletion mutations swept to fixation within ~1000 generations, which is over two million times faster than expected if this deletion was instead selectively neutral and thus evolving by genetic drift. Because flagella are energetically expensive to synthesize and operate, we suspect that debilitating their construction conferred a fitness advantage in our well-stirred evolution experiment. These findings underscore the important role that IS elements can play in mediating adaptive loss-of-function mutations in bacteria.
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DOI：
10.1073/pnas.1210309109
发表时间：
2012-10-09
影响因子：
11.1
作者：
Lee, Heewook;Popodi, Ellen;Foster, Patricia L.
通讯作者：
Foster, Patricia L.
影响因子：
4.5
作者：
Hottes AK;Freddolino PL;Khare A;Donnell ZN;Liu JC;Tavazoie S
通讯作者：
Tavazoie S
影响因子：
3.2
作者：
Barker, CS;Prüss, BM;Matsumura, P
通讯作者：
Matsumura, P
影响因子：
14.9
作者：
Keseler IM;Mackie A;Peralta-Gil M;Santos-Zavaleta A;Gama-Castro S;Bonavides-Martínez C;Fulcher C;Huerta AM;Kothari A;Krummenacker M;Latendresse M;Muñiz-Rascado L;Ong Q;Paley S;Schröder I;Shearer AG;Subhraveti P;Travers M;Weerasinghe D;Weiss V;Collado-Vides J;Gunsalus RP;Paulsen I;Karp PD
通讯作者：
Karp PD
影响因子：
3.2
作者：
Cooper, VS;Schneider, D;Lenski, RE
通讯作者：
Lenski, RE