Cytogenetic Markers in Wild Population of Curimbata (Prochilodus lineatus) from Mogi-Guacu River

Abstract

Summary Within the genus Prochilodus, the species Prochilodus lineatus is certainly the most studied one from a cytogenetic point of view. In this study, a cytogenetic characterization of specimens of P. lineatus from Mogi-Guaçu River was performed in the period from 2003 to 2007, through utilization of cytogenetic markers, such as Giemsa, Ag-NOR, C-banding and cytogeneticalmolecular markers (FISH) to detect both 5S and 18S ribosomal genes. All analyzed individuals presented 2nϭ54 meta/submetacentric chromosomes, besides bearing up to 7 supernumerary microchromosomes. Polymorphic NORs were detected on a single chromosomal pair. The constitutive heterochromatin was distributed at centromeric region of all chromosomes in the A complement, while the microchromosomes were totally heterochromatic. A syntenic distribution of 5S and 18S ribosomal genes was detected, comprising the NOR-bearing chromosomal pair. No additional ribosomal clusters in other chromosomes were observed. Although the karyotype features are commonly conserved within the genus Prochilodus, the few differences on the distribution of both ribosomal genes and heterochromatin when compared to specimens of P. lineatus from other localities can be associated to the evolutionary changes that these repetitive sequences have undergone through the years.

Karyotypic conservatism in five species of Prochilodus (Characiformes, Prochilodontidae) disclosed by cytogenetic markers

“…However, a few populations and/or, species, such as P. brevis , P. lineatus , P. mariae and P. nigricans, showed karyotypic variation due to the presence of supernumerary chromosomes (Pauls and Bertollo 1983, 1990; Oliveira et al , 1997, 2003; Dias et al , 1998; Venere et al , 1999; Maistro et al , 2000; Cavallaro et al , 2000; Jesus and Moreira-Filho, 2003; Artoni et al , 2006; Voltolin et al , 2009). …”

“…Conventional cytogenetic markers, such Ag-NORs, evidenced a single chromosome pair bearing NORs in some species of Prochilodus (Pauls and Bertollo, 1990; Venere et al , 1999; Oliveira et al , 2003; Jesus and Moreira-Filho, 2003; Vicari et al , 2006; Voltolin et al , 2009). …”

“…FISH with the 5S and 18S ribosomal genes showed that they are syntenic in P. lineatus and P. argenteus , and evidenced a polymorphism in the number of 18S rRNA genes (Jesus and Moreira-Filho, 2003; Hatanaka and Galetti Jr, 2004; Voltolin et al , 2009). …”

“…C-banding analyses carried out in Prochilodontidade representatives showed that the constitutive heterochromatin is frequently restricted to centromeric blocks in all chromosomes of the standard (A) complement (Pauls and Bertollo, 1990; Venere et al , 1999; Cavallaro et al , 2000; Oliveira et al , 2003; Jesus and Moreira-Filho 2003; Artoni et al , 2006; Voltolin et al , 2009). Additionally, the supernumerary chromosomes were usually entirely heterochromatic in these species (Pauls and Bertollo 1990; Maistro et al , 2000; Cavallaro et al , 2000; Jesus and Moreira-Filho, 2003; Artoni et al , 2006; Voltolin et al , 2009).…”

First cytogenetic analysis of Ichthyoelephas humeralis (Günther, 1860) by conventional and molecular methods with comments on the karyotypic evolution in Prochilodontidae

“…Ribosomal sites in Prochilodontidae (5S and 18S ribosomal clusters) are syntenic, commonly located in the interstitial position on chromosome pair 2 in all species of Prochilodus and Semaprochilodus analyzed (Pauls and Bertollo 1990, Oliveira et al 1997, 2003; Venere et al 1999, Cavallaro et al 2000, Maistro et al 2000, Jesus and Moreira-Filho 2003, Hatanaka and Galetti Jr. 2004, Artoni et al 2006, Vicari et al 2006, Gras et al 2007, Voltolin et al 2009, 2013, Jorge et al 2011, Terencio et al 2012a, 2012b, Penitente et al 2015). …”