title: Gene mapping of 18S and 5S rDNA genes in the karyotype of the three-spot gourami Trichogaster trichopterus (Perciformes, Osphronemidae).
abstract: Ornamental fish culture is important as an economic activity and for biodiversity conservation as well. The species of the genus Trichogaster (Perciformes, Osphronemidae), popularly known as three-spot gourami, are among the several commercial species raised around the world. In the present work, eight specimens of Thrichogaster trichopterus from aquarium trade facilities were analyzed. The karyotype was composed of 23 pairs of subtelo/acrocentric chromosomes. Fluorescent in situ hybridization allowed identifying the 18S ribosomal gene at telomeric region on long arms of the largest acrocentric pair. On the other hand, the 5S rRNA gene is located at a proximal region on a pair of medium-sized chromosomes. Such information is extremely useful in face of the risks of introduction and the development of ornamental fish trade, once many fish species can be identified only by genetic studies.
authors.affiliation: Campus Rio Paranaíba, Universidade Federal de Viçosa, Rio Paranaíba, Brazil. rpazza@ufv.br
authors.forename: Rubens
authors.initials: R
authors.lastname: Pazza
authors.forename: Karine Frehner
authors.initials: KF
authors.lastname: Kavalco
authors.forename: Pierre Rafael
authors.initials: PR
authors.lastname: Penteado
authors.forename: Sydney Antonio Frehner
authors.initials: SA
authors.lastname: Kavalco
authors.forename: Lurdes Foresti
authors.initials: LF
authors.lastname: de Almeida-Toledo
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D002875:Chromosomes; D007621:Karyotyping; D010473:Perciformes / Q000235:genetics*; D012337:RNA, Ribosomal, 18S / Q000235:genetics*; D012341:RNA, Ribosomal, 5S / Q000235:genetics*
chemical_list: D012337:RNA, Ribosomal, 18S; D012341:RNA, Ribosomal, 5S