The evolution of haploid chromosome numbers in Meliponini
Autoři:
Natália Martins Travenzoli aff001; Danon Clemes Cardoso aff002; Hugo de Azevedo Werneck aff003; Tânia Maria Fernandes-Salomão aff002; Mara Garcia Tavares aff003; Denilce Meneses Lopes aff001
Působiště autorů:
Laboratório de Citogenética de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, CEP, Viçosa, Minas Gerais, Brazil
aff001; Laboratório de Genética Evolutiva e de Populações, Departamento de Biodiversidade, Evolução e Meio Ambiente, Universidade Federal de Ouro Preto, CEP, Ouro Preto, Minas Gerais, Brazil
aff002; Laboratório de Biologia Molecular de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, CEP, Viçosa, Minas Gerais, Brazil
aff003
Vyšlo v časopise:
PLoS ONE 14(10)
Kategorie:
Research Article
prolekare.web.journal.doi_sk:
https://doi.org/10.1371/journal.pone.0224463
Souhrn
It is thought that two evolutionary mechanisms gave rise to chromosomal variation in bees: the first one points to polyploidy as the main cause of chromosomal evolution, while the second, Minimum Interaction Theory (MIT), is more frequently used to explain chromosomal changes in Meliponini and suggests that centric fission is responsible for variations in karyotype. However, differences in chromosome number between Meliponini and its sister taxa and in the karyotype patterns of the Melipona genus cannot be explained by MIT, suggesting that other events were involved in chromosomal evolution. Thus, we assembled cytogenetical and molecular information to reconstruct an ancestral chromosome number for Meliponini and its sister group, Bombini, and propose a hypothesis to explain the evolutionary pathways underpinning chromosomal changes in Meliponini. We hypothesize that the common ancestor shared by the Meliponini and Bombini tribes possessed a chromosome number of n = 18. The karyotype with n = 17 chromosomes was maintained in Meliponini, and variations of haploid numbers possibly originated through additional Robertsonian fissions and fusions. Thus, the low chromosome number would not be an ancestral condition, as predicted by MIT. We then conclude that Robertsonian fission and fusions are unlikely to be the cause of chromosomal rearrangements that originated the current karyotypes in Meliponini.
Klíčová slova:
Phylogenetics – Phylogenetic analysis – Chromosome structure and function – Sequence databases – Bees – Karyotypes – Cytogenetics – Heterochromatin
Zdroje
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