Abstract:
The Maipo River catchment is one of Chile\'s most polluted basins. In recent decades, discharges of untreated sewage and organic matter have caused eutrophication and water quality degradation. We employed the indigenous silverfish species Basilichthys microlepidotus as a model organism to investigate the process of adaptation and selection on genes influenced by pollution. Using variation at single nucleotide polymorphisms (SNPs), we determined the temporal stability of the population structure patterns previously identified in this species by varying SNPs. We also examined local adaptation to pollution-selected genes. Using the genotypes of 7684 loci in 180 individuals, we identified 429 and 700 loci that may be undergoing selection. We detected these loci using the FSTHET and ARLEQUIN outlier detection software, respectively. Both software packages simultaneously identified a total of 250 loci. B. microlepidotus\' population structure did not change over time at contaminated or unpolluted sites. In addition, our analysis found: (i) selection of genes associated with pollution, consistent with observations in other organisms; (ii) identification of candidate genes that are functionally linked to the same biological processes, molecular functions and/or cellular components that previously showed differential expression in the same populations; and (iii) a candidate gene with differential expression and a non-synonymous substitution.
摘要:
迈波河流域是智利污染最严重的流域之一。近几十年来,未经处理的污水和有机物的排放导致了富营养化和水质恶化。我们采用本地银鱼物种Basilichthysmicrolepidotus作为模型生物,以研究受污染影响的基因的适应和选择过程。利用单核苷酸多态性(SNPs)的变异,我们通过改变SNP确定了先前在该物种中鉴定的种群结构模式的时间稳定性。我们还研究了对污染选择基因的局部适应性。使用180个个体的7684个基因座的基因型,我们确定了可能正在进行选择的429个和700个基因座.我们使用FSTHET和ARLEQUIN异常检测软件检测了这些基因座,分别。两个软件包同时识别总共250个基因座。在受污染或未污染的地点,微鳞茎芽孢杆菌的种群结构没有随时间变化。此外,我们的分析发现:(I)选择与污染相关的基因,与其他生物体的观察结果一致;(ii)鉴定与相同生物过程功能相关的候选基因,先前在相同群体中显示差异表达的分子功能和/或细胞组分;和(iii)具有差异表达和非同义取代的候选基因。