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Bertollo, Luiz Antônio Carlos; Born, Guassenir Gonçalves; Dergam, Jorge Abdala; Fenocchio, Alberto Sérgio; Moreira‐Filho, Orlando

doi:10.1023/a:1009233907558

Cited by 153 publications

(81 citation statements)

References 4 publications

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“…This same scenario is also found with the Neotropical fish Hoplias malabaricus (Erythrinidae), which represents a “species complex” with a wide geographic distribution and a low vagility. This fish is outstanding in its karyotypic diversity, with well-defined population differences in diploid numbers and chromosomal morphology and distinct sex chromosome systems [33,34]. …”

Section: Discussionmentioning

confidence: 99%

Genomic Organization of Repetitive DNA Elements and Its Implications for the Chromosomal Evolution of Channid Fishes (Actinopterygii, Perciformes)

et al. 2015

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Channid fishes, commonly referred to as “snakeheads”, are currently very important in Asian fishery and aquaculture due to the substantial decline in natural populations because of overexploitation. A large degree of chromosomal variation has been found in this family, mainly through the use of conventional cytogenetic investigations. In this study, we analyzed the karyotype structure and the distribution of 7 repetitive DNA sequences in several Channa species from different Thailand river basins. The aim of this study was to investigate the chromosomal differentiation among species and populations to improve upon the knowledge of its biodiversity and evolutionary history. Rearrangements, such as pericentric inversions, fusions and polyploidization, appear to be important events during the karyotypic evolution of this genus, resulting in the chromosomal diversity observed among the distinct species and even among populations of the same species. In addition, such variability is also increased by the genomic dynamism of repetitive elements, particularly by the differential distribution and accumulation of rDNA sequences on chromosomes. This marked diversity is likely linked to the lifestyle of the snakehead fishes and their population fragmentation, as already identified for other fish species. The karyotypic features highlight the biodiversity of the channid fishes and justify a taxonomic revision of the genus Channa, as well as of the Channidae family as a whole, as some nominal species may actually constitute species complexes.

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Section: Discussionmentioning

confidence: 99%

Genomic Organization of Repetitive DNA Elements and Its Implications for the Chromosomal Evolution of Channid Fishes (Actinopterygii, Perciformes)

et al. 2015

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“…Cytogenetic studies with samples from different areas have shown that many local populations have distinct karyotypic characteristics, which suggested that several unidentifiable species were actually observed instead of a single widely distributed species (Bertollo et al 1978(Bertollo et al , 1979(Bertollo et al , 2000Morelli et al 1983;Giuliano-Caetano and Bertollo 1988;Oliveira et al 1990;Moreira-Filho and Bertollo 1991;Maistro et al 1992;Cestari and Galetti 1992;Porto and Feldberg 1992;Andreata et al 1993;Moreira-Filho et al 2004).…”

Section: Occurrence Of Cryptic Species and Species Complexesmentioning

confidence: 99%

Genetics of neotropical fish: from chromosomes to populations

Oliveira

Foresti

Hilsdorf

2008

Fish Physiol Biochem

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The Neotropical freshwater fish fauna is very rich--according to the most recent catalogue 71 families and 4,475 species have been described. However, only a small amount of general information is available on the composition of Neotropical marine fishes. In Brazil, 1,298 marine species have been recorded. General analysis of available cytogenetic and population genetic data clearly indicates research has been mainly concentrated on freshwater fishes. Thus, today, cytogenetic information is available for 475 species of Characiformes, 318 species of Siluriformes, 48 species of Gymnotiformes, 199 freshwater species that do not belong to the superorder Ostariophysi, and only 109 species of marine fishes. For the species studied, only about 6% have sex chromosomes and about 5% have supernumerary or B chromosomes. A review of the cytogenetic studies shows that these data have provided valuable information about the relationships between fish groups, the occurrence of cryptic species and species complexes, the mechanism of sex determination and sex chromosome evolution, the distribution of nucleolus organizer regions, the existence supernumerary chromosomes, and the relationship between polyploidy and evolution. In relation to populations in Neotropical marine waters, the studies have shown the presence of cryptic species, which has important implications for fishery management. Different levels of genetic structuring can be found among Neotropical freshwater migratory fish species. This raises important implications for fish population genetic diversity and consequently its sustainable utilization in inland fisheries and aquaculture, specifically for conservation of ichthyo-diversity and survival.

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“…Among the species of this group, Hoplias malabaricus (Bloch, 1794) and Erythrinus erythrinus (Bloch & Schneider, 1801) present a great diversity of karyomorphs and differentiated sex chromosome systems (Bertollo et al 2000, Bertollo et al 2004). In fact, four karyomorphs (A to D) were already described for Erythrinus erythrinus , and with exception of karyomorph A that not have differentiated sex chromosomes, the karyomorphs B, C and D share an X 1 X 1 X 2 X 2 /X 1 X 2 Y multiple sex system, but with different diploid numbers and chromosome morphology (Bertollo et al 2004).…”

Section: Introductionmentioning

confidence: 99%

Genomic organization of repetitive DNAs and its implications for male karyotype and the neo-Y chromosome differentiation in Erythrinus erythrinus (Characiformes, Erythrinidae)

Yano¹,

Bertollo²,

Molina³

et al. 2014

CCG

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Studies have demonstrated the effective participation of repetitive DNA sequences in the origin and differentiation of the sex chromosomes in some biological groups. In this study several microsatellites and retrotranposable sequences were cytogenetically mapped in the Erythrinus erythrinus (Bloch & Schneider, 1801) male genome (karyomorph C), focusing on the distribution of these sequences in the sex chromosomes and in the evolutionary processes related to their differentiation. Males of E. erythrinus – karyomorph C – present 2n = 51 chromosomes (7m + 2sm + 6st + 36a), including the X1X2Y sex chromosomes. The C-positive heterochromatin has a predominant localization on the centromeric region of most chromosome pairs, but also in some telomeric regions. The 5S rDNA sites are located in the centromeric region of 27 chromosomes, including 26 acrocentric ones and the metacentric Y chromosome. The retrotransposons Rex 1 and Rex 6 show a dispersed pattern in the karyotype, contrasting with the Rex 3 distribution which is clearly co-localized with all the 27 5S rDNA sites. The microsatellite sequences show a differential distribution, some of them restricted to telomeric and/or interstitial regions and others with a scattered distribution on the chromosomes. However, no preferential accumulation of these elements were observed in the neo-Y chromosome, in contrast to what usually occurs in simple sex chromosome systems.

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Cited by 153 publications

References 4 publications

Genomic Organization of Repetitive DNA Elements and Its Implications for the Chromosomal Evolution of Channid Fishes (Actinopterygii, Perciformes)

Genomic Organization of Repetitive DNA Elements and Its Implications for the Chromosomal Evolution of Channid Fishes (Actinopterygii, Perciformes)

Genetics of neotropical fish: from chromosomes to populations

Genomic organization of repetitive DNAs and its implications for male karyotype and the neo-Y chromosome differentiation in Erythrinus erythrinus (Characiformes, Erythrinidae)

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