Caracterização citogenética e molecular das espécies Cichla kelberi e Cichla piquiti e seu possível híbrido interespecífico coletados em ambientes naturais

• Autor(a) principal: Mourão, Andrea Abrigato de Freitas [UNESP]
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/108591
• topic: Peixe - Genetica; Expressão gênica; Peixe - Identificação; Citogenetica; Peixe - Classificação; Fishes Classification

Some invasive species are highly efficient in resource competition, have high reproductive capacity and dispersal, the genus Cichla exemplifies these characteristics. The specimens of this genus are widely used to control exotic species with high prolificacy, beyond its undeniable importance in food and sport fishing. In the present study, the chromosomal and genetic differentiation between species Cichla kelberi and Cichla piquiti and its likely natural hybrids. We used cytogenetic techniques and molecular markers PCR multiplex and PCR-­‐RFLP with nuclear and mitochondrial genes and, subsequently, the markers were applied to specimens collected in rivers Parana and Tiete in São Paulo. The cytogenetic techniques were performed for samples collected from the river Tiete, Uru city, while for the establishment and application of molecular markers were used samples of both cities, river Parana (Uru) and river Tiete (Rubineia, Pauliceia e Ilha Solteira). The cytogenetic results indicate a karyotype conservation between species Cichla piquiti and Cichla kelberi such species have diploid number of 2n=48 chromosomes acrocentric type, located nucleolus organizer regions in the pair 2 and constitutive heterochromatic centromeric regions. Furthermore, ribosomal genes are located on the same chromosome pairs for both species, but the 5S rDNA located on the third chromosome pair in interstitial position, and 18S rDNA corroborating markings NOR. Already in the molecular analysis, genomic differences were established between the species C. kelberi and C. piquiti, which allowed the establishment of efficient applicability markers for differentiation of the two species and in different populations, a fact confirmed by applying the same samples from four locations in the state of São Paulo. Furthermore, such genetic markers indicate that the samples identified as hybrid individuals of the species C. kelberi and C. piquiti are actually ...