title: A High-Resolution Comparative Chromosome Map of Cricetus cricetus and Peromyscus eremicus Reveals the Involvement of Constitutive Heterochromatin in Breakpoint Regions.
abstract: Compared to humans and other mammals, rodent genomes, specifically Muroidea species, underwent intense chromosome reshuffling in which many complex structural rearrangements occurred. This fact makes them preferential animal models for studying the process of karyotype evolution. Here, we present the first combined chromosome comparative maps between 2 Cricetidae species, Cricetus cricetus and Peromyscus eremicus, and the index species Mus musculus and Rattus norvegicus. Comparative chromosome painting was done using mouse and rat paint probes together with in silico analysis from the Ensembl genome browser database. Hereby, evolutionary events (inter- and intrachromosomal rearrangements) that occurred in C. cricetus and P. eremicus since the putative ancestral Muroidea genome could be inferred, and evolutionary breakpoint regions could be detected. A colocalization of constitutive heterochromatin and evolutionary breakpoint regions in each genome was observed. Our results suggest the involvement of constitutive heterochromatin in karyotype restructuring of these species, despite the different levels of conservation of the C. cricetus (derivative) and P. eremicus (conserved) genomes.
authors.affiliation: Center of Agricultural and Genomics Biotechnology (CGBA), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Vieira-da-Silva
authors.forename: Sandra
authors.initials: S
authors.lastname: Louzada
authors.forename: Filomena
authors.initials: F
authors.lastname: Adega
authors.forename: Raquel
authors.initials: R
authors.lastname: Chaves
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D056905:Chromosome Breakpoints; D002874:Chromosome Mapping; D020223:Chromosome Painting; D033481:Chromosomes, Mammalian / Q000235:genetics; D006224:Cricetinae / Q000235:genetics*; D019143:Evolution, Molecular; D015321:Gene Rearrangement / Q000235:genetics*; D016678:Genome / Q000235:genetics; D006570:Heterochromatin / Q000235:genetics*; D017404:In Situ Hybridization, Fluorescence; D059785:Karyotype; D051379:Mice; D010542:Peromyscus / Q000235:genetics*; D051381:Rats
chemical_list: D006570:Heterochromatin