Mitochondrial phylogeography and molecular evolution of the rhodopsin visual pigment in troglobitic populations of Astyanax mexicanus(De Filippi,1853)  

作　　者：Marco A.A.Garduño-Sánchez Vladimir de Jesus-Bonilla Silvia Perea Ramses Miranda-Gamboa Andrea Herrera-García Mauricio de la Maza Benignos Claudia Patricia Ornelas-García 

机构地区：[1]Colección Nacional de Peces,Departamento de Zoología,Instituto de Biología,Universidad Nacional Autónoma de México,Ciudad de México,C.P.04510,México [2]Posgrado en Ciencias Biológicas,Colección Nacional de Peces,Departamento de Zoología,Instituto de Biología,Universidad Nacional Autónoma de México,Ciudad de México,C.P.04510,México [3]Licenciatura en Ciencias Forenses,Facultad de Medicina,Universidad Nacional Autónoma de México,Ciudad Universitaria,Coyoacán,México City,C.P.04510,México [4]Instituto de Energías Renovables,Universidad Nacional Autónoma de México,Temixco,Morelos C.P.62580,Mexico [5]Facultad de Ciencias Biológicas,Universidad Autónoma de Nuevo León,Ciudad Universitaria,San Nicolás de los Garza,Nuevo León,C.P.66450,México

出　　处：《Zoological Research》2023年第4期761-775,共15页动物学研究（英文）

基　　金：supported by the Project No.191986,Fronteras de la Ciencia-CONACyT;Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica(PAPIIT),UNAM No.IN212419。

摘　　要：Cave-adapted animals provide a unique opportunity to study the evolutionary mechanisms underlying phenotypic,metabolic,behavioral,and genetic evolution in response to cave environments.The Mexican tetra(Astyanax mexicanus)is considered a unique model system as it shows both surface and cave-dwelling morphs.To date,at least 33 different cave populations have been identified,with phylogenetic studies suggesting an origin from at least two independent surface lineages,thereby providing a unique opportunity to study parallel evolution.In the present study,we carried out the most exhaustive phylogeographic study of A.mexicanus to date,including cave and surface localities,using two mitochondrial markers(cytochrome b(cyt b)and cytochrome c oxidase subunit I(COI))and nuclear rhodopsin visual pigment(rho).Additionally,we inferred the molecular evolution of rho within the two contrasting environments(cave and surface)and across three geographic regions(Sierra de El Abra,Sierra de Guatemala,and Micos).In total,267 individuals were sequenced for the two mitochondrial fragments and 268 individuals were sequenced for the rho visual pigment from 22 cave and 46 surface populations.Phylogeographic results based on the mitochondrial data supported the two-lineage hypothesis,except for the Pachón and Chica caves,whose introgression has been largely documented.The Sierra de El Abra region depicted the largest genetic diversity,followed by the Sierra de Guatemala region.Regarding the phylogeographic patterns of rho,we recovered exclusive haplogroups for the Sierra de El Abra(Haplogroup I)and Sierra de Guatemala regions(Haplogroup IV).Moreover,a 544 bp deletion in the rho gene was observed in the Escondido cave population from Sierra de Guatemala,reducing the protein from seven to three intramembrane domains.This change may produce a loss-of-function(LOF)but requires further investigation.Regarding nonsynonymous(dN)and synonymous(dS)substitution rates(omega valuesω),our results revealed the prevailing influence of purifying selecti

关 键 词：Visual pigments Selection CAVEFISH Vision loss Loss of function 

分 类 号：Q958[生物学—动物学]