title: Clues on Syntenic Relationship among Some Species of Oryzomyini and Akodontini Tribes (Rodentia: Sigmodontinae).
abstract: Sigmodontinae rodents represent one of the most diverse and complex components of the mammalian fauna of South America. Among them most species belongs to Oryzomyini and Akodontini tribes. The highly specific diversification observed in both tribes is characterized by diploid complements, which vary from 2n = 10 to 86. Given this diversity, a consistent hypothesis about the origin and evolution of chromosomes depends on the correct establishment of synteny analyzed in a suitable phylogenetic framework. The chromosome painting technique has been particularly useful for identifying chromosomal synteny. In order to extend our knowledge of the homeological relationships between Akodontini and Oryzomyini species, we analyzed the species Akodon montensis (2n = 24) and Thaptomys nigrita (2n = 52) both from the tribe Akodontini, with chromosome probes of Hylaeamys megacephalus (2n = 54) of the tribe Oryzomyini. The results indicate that at least 12 of the 26 autosomes of H. megacephalus show conserved synteny in A. montensis and 14 in T. nigrita. The karyotype of Akodon montensis, as well as some species of the Akodon cursor species group, results from many chromosomal fusions and therefore the syntenic associations observed probably represent synapomorphies. Our finding of a set of such associations revealed by H. megacephalus chromosome probes (6/21; 3/25; 11/16/17; and, 14/19) provides phylogenetic information for both tribes. An extension of these observations to other members of Akodontini and Oryzomyini tribes should improve our knowledge about chromosome evolution in both these groups.
authors.affiliation: Laboratório de Citogenética, Centro de Estudos Avançados da Biodiversidade, ICB, UFPa, Belém, Pará, Brazil.
authors.forename: Pablo
authors.initials: P
authors.lastname: Suárez
authors.affiliation: Laboratório de Citogenética, Centro de Estudos Avançados da Biodiversidade, ICB, UFPa, Belém, Pará, Brazil.|CNPq Researchers, Brasilia, Brazil.
authors.forename: Cleusa Yoshiko
authors.initials: CY
authors.lastname: Nagamachi
authors.affiliation: Laboratorio de Genética Evolutiva, IBS, FCEQyN, CONICET-UNaM, Posadas, Misiones, Argentina.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Lanzone
authors.affiliation: Laboratorio de Genética Evolutiva, IBS, FCEQyN, CONICET-UNaM, Posadas, Misiones, Argentina.
authors.forename: Matias Maximiliano
authors.initials: MM
authors.lastname: Malleret
authors.affiliation: Cambridge Resource Centre for Comparative Genomics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Patricia Caroline Mary
authors.initials: PC
authors.lastname: O'Brien
authors.affiliation: Cambridge Resource Centre for Comparative Genomics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Malcolm Andrew
authors.initials: MA
authors.lastname: Ferguson-Smith
authors.affiliation: Laboratório de Citogenética, Centro de Estudos Avançados da Biodiversidade, ICB, UFPa, Belém, Pará, Brazil.|CNPq Researchers, Brasilia, Brazil.
authors.forename: Julio Cesar
authors.initials: JC
authors.lastname: Pieczarka
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002871:Chromosome Banding; D020223:Chromosome Painting; D015342:DNA Probes; D010802:Phylogeny; D016205:Sigmodontinae / Q000235:genetics*; D013020:South America; D013045:Species Specificity; D026801:Synteny
chemical_list: D015342:DNA Probes