Long-term persistence of supernumerary B chromosomes in multiple species of Astyanax fish

BMC Biology

Diogo T. Hashimoto¹  Robson Francisco Carvalho²  Claudio Oliveira²  Duílio Mazzoni Zerbinato de Andrade Silva²  Fausto Foresti²  Paula Paccielli Freire³  Fábio Porto-Foresti⁴  Roberto Ferreira Artoni⁵  Jonathan Pena Castro⁵  Ricardo Utsunomia⁶  María Martín-Peciña⁷  Juan Pedro M. Camacho⁷  Francisco J. Ruiz-Ruano⁸  Alexander Suh⁹ 

[1] Centro de Aquicultura, Universidade Estadual Paulista, UNESP, Campus Jaboticabal, 14884-900, Jaboticabal, SP, Brazil;Departamento de Biologia Estrutural e Funcional, Instituto de Biociências de Botucatu, Universidade Estadual Paulista, UNESP, Distrito de Rubião Junior, 18618-970, Botucatu, SP, Brazil;Departamento de Biologia Estrutural e Funcional, Instituto de Biociências de Botucatu, Universidade Estadual Paulista, UNESP, Distrito de Rubião Junior, 18618-970, Botucatu, SP, Brazil;Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, USP, 05508-900, São Paulo, SP, Brazil;Departamento de Ciências Biológicas, Faculdade de Ciências, Universidade Estadual Paulista, UNESP, Campus de Bauru, 17033-360, Bauru, SP, Brazil;Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCAR, 13565-905, São Carlos, SP, Brazil;Departamento de Biologia Estrutural, Molecular e Genética, Universidade Estadual de Ponta Grossa, UEPG, 84030-900, Ponta Grossa, PR, Brazil;Departamento de Genética, Instituto de Ciências Biológicas e da Saúde, ICBS, Universidade Federal Rural do Rio de Janeiro, 23897-000, Seropédica, RJ, Brazil;Departamento de Ciências Biológicas, Faculdade de Ciências, Universidade Estadual Paulista, UNESP, Campus de Bauru, 17033-360, Bauru, SP, Brazil;Departamento de Genética, Universidad de Granada, 18071, Granada, Spain;Department of Organismal Biology – Systematic Biology, Evolutionary Biology Centre, Uppsala University, SE-752 36, Uppsala, Sweden;Departamento de Genética, Universidad de Granada, 18071, Granada, Spain;School of Biological Sciences, University of East Anglia, Norwich Research Park, NR4 7TU, Norwich, UK;Department of Organismal Biology – Systematic Biology, Evolutionary Biology Centre, Uppsala University, SE-752 36, Uppsala, Sweden;School of Biological Sciences, University of East Anglia, Norwich Research Park, NR4 7TU, Norwich, UK;

关键词: B chromosomes;    Astyanax;    Evolution;    Genomics;    Transcriptomics;   

DOI  :  10.1186/s12915-021-00991-9

来源: Springer

【 摘 要 】

BackgroundEukaryote genomes frequently harbor supernumerary B chromosomes in addition to the “standard” A chromosome set. B chromosomes are thought to arise as byproducts of genome rearrangements and have mostly been considered intraspecific oddities. However, their evolutionary transcendence beyond species level has remained untested.ResultsHere we reveal that the large metacentric B chromosomes reported in several fish species of the genus Astyanax arose in a common ancestor at least 4 million years ago. We generated transcriptomes of A. scabripinnis and A. paranae 0B and 1B individuals and used these assemblies as a reference for mapping all gDNA and RNA libraries to quantify coverage differences between B-lacking and B-carrying genomes. We show that the B chromosomes of A. scabripinnis and A. paranae share 19 protein-coding genes, of which 14 and 11 were also present in the B chromosomes of A. bockmanni and A. fasciatus, respectively. Our search for B-specific single-nucleotide polymorphisms (SNPs) identified the presence of B-derived transcripts in B-carrying ovaries, 80% of which belonged to nobox, a gene involved in oogenesis regulation. Importantly, the B chromosome nobox paralog is expressed > 30× more than the A chromosome paralog. This indicates that the normal regulation of this gene is altered in B-carrying females, which could potentially facilitate B inheritance at higher rates than Mendelian law prediction.ConclusionsTaken together, our results demonstrate the long-term survival of B chromosomes despite their lack of regular pairing and segregation during meiosis and that they can endure episodes of population divergence leading to species formation.

【 授权许可】

CC BY