Adaptive evolution in the SRZ chemoreceptor families of Caenorhabditis elegans and Caenorhabditis briggsae.
Adaptive evolution in the SRZ chemoreceptor families of Caenorhabditis elegans and Caenorhabditis briggsae.
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秀丽隐杆线虫和布里格萨斯 SRZ 化学感受器家族的适应性进化。
DOI：
10.1073/pnas.0406469102
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Swanson,WillieJ
中科院分区：
文献类型：
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作者：
Thomas,JamesH;Kelley,JoannaL;Robertson,HughM;Ly,Kim;Swanson,WillieJ
我们研究了正选择作用于秀丽隐杆线虫七通道化学感受器超家族成员的可能性，该超家族由1,300个编码七通道G蛋白偶联受体（GPCR）的基因组成。使用最大似然法，我们对每个非同义位点的非同义取代与每个同义位点的同义取代之比（dN/dS）>1的密码子位点的证据进行了统计检验。阳性选择的证据只在rz家族中发现，而关于这个家族，实际上没有任何具体的东西是已知的。我们扩展了srz基因家族的注释，建立了60个C.在SRZ蛋白的不同区域，dN/dS比值变化很大，在预测的细胞外区域达到峰值。这些区域包括23个位点，其中阳性选择的证据非常显著，与其他GPCR家族成员中涉及配体结合的区域非常好地对应。我们解释这些结果表明，thesrz家庭是积极的选择，可能是由配体结合。
We investigated the possibility of positive selection acting on members of the putative seven-pass chemoreceptor superfamily inCaenorhabditis elegans, which comprises ≈1,300 genes encoding seven-pass G protein-coupled receptors (GPCRs). Using a maximum-likelihood approach, we conducted statistical tests for evidence of codon sites where the ratio of nonsynonymous substitutions per nonsynonymous site to synonymous substitutions per synonymous site (dN/dS) was >1. Evidence for positive selection was found only for thesrzfamily, about which virtually nothing specific is known. We extended the annotation of thesrzgene family, establishing gene models for 60srzgenes inC. elegansand 28srzgenes inCaenorhabditis briggsae.dN/dSratios varied dramatically in different regions of the SRZ proteins, peaking in predicted extracellular regions. These regions included 23 sites where evidence of positive selection was highly significant, corresponding remarkably well with regions implicated in ligand binding in other GPCR family members. We interpret these results as indicating that thesrzfamily is under positive selection, probably driven by ligand binding.