title: Chromosome Mapping of 18S Ribosomal RNA Genes in Eleven Hypostomus Species (Siluriformes, Loricariidae): Diversity Analysis of the Sites.
abstract: We investigated the chromosomal distribution of 18S ribosomal DNA (rDNA) in different populations of 11 species of Hypostomus collected in important Brazilian basins, namely South Atlantic, Upper Paraná, and Paraguay applying the fluorescence in situ hybridization (FISH). Hypostomus cochliodon, Hypostomus commersoni, Hypostomus hermanni, Hypostomus regani, Hypostomus albopunctatus, Hypostomus paulinus, Hypostomus aff. paulinus, Hypostomus iheringii, and Hypostomus mutucae presented multiple 18S rDNA sites while Hypostomus strigaticeps and Hypostomus nigromaculatus exhibited a single pair of chromosomes with 18S rDNA sites. The studied species presented variations in the number and position of these sites. The results accomplished were similar to those obtained by the analysis of AgNORs, revealing the same interspecific variability. Each species exhibited distinctive patterns of AgNOR and 18S rDNA distribution, which can be considered cytogenetic markers in each species of the genus and help improve the discussions on the phylogeny of the group.
authors.affiliation: 1 Laboratório de Biodiversidade Molecular e Conservação, Universidade Federal de São Carlos , São Carlos, Brazil .
authors.forename: Marceléia
authors.initials: M
authors.lastname: Rubert
authors.affiliation: 2 Laboratório de Citogenética Animal, Universidade Estadual de Londrina , Londrina, Brazil .
authors.forename: Renata
authors.initials: R
authors.lastname: da Rosa
authors.affiliation: 3 Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura, Universidade Estadual de Maringá , Maringá, Brazil .
authors.forename: Claudio H
authors.initials: CH
authors.lastname: Zawadzki
authors.affiliation: 4 Instituto Federal de Educação Ciência e Tecnologia de Mato Grosso (IFMT) , Cuiabá, Brazil .
authors.forename: Sandra
authors.initials: S
authors.lastname: Mariotto
authors.affiliation: 1 Laboratório de Biodiversidade Molecular e Conservação, Universidade Federal de São Carlos , São Carlos, Brazil .
authors.forename: Orlando
authors.initials: O
authors.lastname: Moreira-Filho
authors.affiliation: 2 Laboratório de Citogenética Animal, Universidade Estadual de Londrina , Londrina, Brazil .
authors.forename: Lucia
authors.initials: L
authors.lastname: Giuliano-Caetano
mesh_terms: D000818:Animals; D002397:Catfishes / Q000235:genetics*; D002874:Chromosome Mapping; D014644:Genetic Variation; D012337:RNA, Ribosomal, 18S / Q000235:genetics*; D013045:Species Specificity
chemical_list: D012337:RNA, Ribosomal, 18S