Corresponding author: Ana Lúcia Dias (
Academic editor: I. Kuznetcova
The family nucleolus organizer regions
Sampaio TR, Pires LB, Venturelli NB, Usso MC, Rosa R, Dias AL (2016) Evolutionary trends in the family Curimatidae (Characiformes): inferences from chromosome banding. Comparative Cytogenetics 10(1): 77–95. doi:
Cytogenetic studies in Neotropical fish reveal great chromosome diversity with both intra- and interspecific karyotype variability. Within the order
Small changes in the karyotype microstructure involving the nucleolus organizer regions
Another feature considered a chromosomal diversification within
Although a number of cytogenetic studies show conservation of the diploid number (2n=54) in the family
Six species of the family
Species, collection sites and hydrographic basins.
Species | Number of individuals | Collection sites | Hydrographic basin |
---|---|---|---|
|
5♀, 6♂ | Três Bocas stream, Londrina, PR, Brazil |
Paranapanema river |
|
1♀, 9♂ | Agronomic Experiment Station of UFRGS’s Dam, Eldorado do Sul, RS, Brazil |
Laguna dos Patos hydrographic system |
|
2♀, 2♂ | Capivara stream, Barra do Ribeiro, RS, Brazil |
|
1♂ | Gasômetro, Porto Alegre, RS, Brazil |
||
|
1♀, 1♂ | Saco da Alemoa river, Eldorado do Sul, RS, Brazil |
|
3♀, 9♂ | Capivara stream, Barra do Ribeiro, RS, Brazil |
||
1♀, 3♂ | Gasômetro, Porto Alegre, RS, Brazil |
||
5♂ | Barros lagoon, Osório, RS, Brazil |
||
3♀, 4♂ | Quadros lagoon – Barra do João Pedro, Maquiné, RS, Brazil |
Tramandaí river | |
|
1♀, 1♂ | Forquetinha river, Canudos do Vale, RS, Brazil |
Laguna dos Patos hydrographic system |
|
3♀, 2♂ | Três Bocas stream, Londrina, PR, Brazil |
Paranapanema river |
2♂ | Pavão stream, Sertanópolis, PR, Brazil | ||
6♀, 12♂ | Jacutinga river, Londrina, PR, Brazil |
||
3♀, 7♂ | Água dos Patos river, Iepê, SP, Brazil |
||
Total of individuals: | 93 |
Mitosis was stimulated by injecting animals with a yeast suspension (
The distribution of heterochromatin was analyzed by C-banding ( Silver nitrate staining of the active nucleolus organizer regions Chromomycin A3 4’,6-diamidino-2-phenylindole
Fluorescence
All species analyzed showed 54 meta-submetacentric chromosomes fundamental number
Karyotypes with B microchromosome of:
Karyotypes with B microchromosome of:
One
Chromosome pairs and positions of the nucleolus organizer regions (AgNORs).
Species | Secondary constriction | ||
---|---|---|---|
|
02 | Terminal/long arm | ------ |
|
08 | Terminal/long arm | ------ |
|
02 | Terminal/long arm | Interstitial/short arm |
|
05 | Terminal/long arm | Terminal/long arm |
|
03 | Terminal/long arm | Terminal/long arm |
|
12 | Terminal/short arm | ------ |
The AgNORs in the species
Two individuals of
Metaphases of
5S rDNA
Heterochromatin in
Metaphases with C-banding of:
Metaphases with C-banding staining with CMA3 of: (
Microchromosome B proved to be heterochromatic in
This study showed the first chromosome banding data for populations of
Chromosome studies in the family
Species | Locality | 2n | Karyotypic formula |
|
Position | Number of cistrons 18S rDNA | Number/position of cistrons 5S rDNA | C banding | Reference | |
---|---|---|---|---|---|---|---|---|---|---|
|
Negro and Solimões river/AM | 54 | 44m + 10sm | 108 | 3 | term. long arm | - | - | - | 3 |
Araguaia river/MT | 54 | 44m + 10sm | 108 | 7 | term. long arm | - | - | - | 16 | |
|
Negro and Solimões river/AM | 54 | 40m + 14sm | 108 | 21 | inters. short arm | - | - | - | 3 |
Araguaia river/MT | 54 | 40m + 14sm | 108 | 3, 22 | term. long arm | - | - | Peric./term. | 16 | |
|
Negro and Solimões river/AM | 54 | 40m + 14sm | 108 | 27 | term. short arm | - | - | - | 3 |
|
Negro and Solimões river/AM | 56 | 40m + 16sm | 112 | 26 | inters. short arm | - | - | - | 3 |
|
Negro and Solimões river/AM | 54 | 42m + 12sm | 108 | 9 | term. long arm | - | - | - | 3 |
|
Negro and Solimões river/AM | 54 | 46m + 8sm | 108 | 14 | term. long arm | - | - | - | 3 |
|
Miranda river/MS | 54 | 46m + 8sm | 108 | 13 | term. short arm | - | - | Peric. | 7 |
Paraná river/AR | 54 | 54m/sm | 108 | 2 | term. long arm | - | - | Centr./term. | 11 | |
|
Araguaia river/GO | 54 | 46m + 8sm | 108 | 24 | inters. long arm | - | - | Peric. | 16 |
|
São Francisco river/SP | 54 | 54m/sm | 108 | 9 | term. short arm | - | - | - | 2 |
|
Negro and Solimões river/AM | 54 | 46m + 8sm | 108 | 9 | term. long arm | - | - | - | 3 |
|
Miranda river/MS | 46 | 42m + 4sm | 92 | - | - | - | - | - | 7 |
|
Paraibuna river/SP | 54 | 44m + 10sm | 108 | 2 | term. short arm | - | - | Peric./term. | 16 |
|
Bento Gomes river/MT | 54 | 54m/sm | 108 | 1 | inters. long arm | - | - | - | 2 |
|
Araguaia river/GO | 54 | 54m + B | 108 | 2 | term. long arm | - | - | Peric. | 16 |
|
Tiête river/SP | 54 | 54m/sm/B | 108 | - | term. long arm | - | - | Centr./term. | 1 |
Águas de São Pedro/SP | 54 | 54m/sm | 108 | 2 | term. long arm | - | - | - | 2 | |
Três Bocas stream/PR | 54 | 54m/sm + B | 108 | 2 | term. long arm | 2 | - | Peric./term. | 6, 13, 15, 18, 19 | |
Mogi-Guaçu river/SP | 54 | 54m/sm + B | 108 | - | - | - | - | Peric. | 8 | |
Taquari river/PR | 54 | 54m/sm + B | 108 | 2 | term. long arm | 2 | - | Peric./term. | 13, 15 | |
Tibagi river/PR | 54 | 54m/sm | 108 | 2 | term. long arm | 2 | - | - | 15 | |
Água da Floresta river/PR | 54 | 54m/sm | 108 | 2 | term. long arm | 2 | - | - | 15 | |
Paranapanema river/SP | 54 | 54m/sm + B | 108 | 2 | term. long arm | 2 | 4/peric. short arm | Centr./term. | 12, 14, 17 | |
Tietê river/SP | 54 | 54m/sm | 108 | 2 | term. long arm | 2 | 4/peric. short arm | Centr./term. | 12, 14, 17 | |
|
Mogi-Guaçu river/SP | 54 | 54m/sm | 108 | 25 | term. short arm | - | - | - | 2 |
Mogi-Guaçu river/SP | 54 | 46m + 8sm | 108 | 1, 2, 6, 11, 21 | term. long /short arm | - | - | Peric./term. | 16 | |
|
Paraná river/AR | 58 | 52m/sm + 6st | 116 | 5 | term. short arm | - | - | Centr. | 11 |
Pirá-Pytá stream/ AR | 58 | 48m + 4 sm + 6st | 116 | 6 | term. short arm | - | - | Peric./term. | 16 | |
|
Madeira river/RO | 54 | 54m/sm | 108 | 10 | term. long arm | - | - | - | 2 |
|
Paraná river/AR | 54 | 54m/sm + B | 108 | 1 | inters. long arm | - | - | Centr./term. | 10, 11 |
Capivara stream/RS | 54 | 54m/sm + B | 108 | 2 | term. long arm | 2 | - | Peric./term. | 18, 19 | |
Gasômetro/RS | 54 | 54m/sm + B | 108 | 2 | term. long arm | 2 | 3/peric. short arm | Peric./term. | 18, 19 | |
|
Preto river/SP | 54 | 54m/sm | 108 | 6 | term. long arm | - | - | - | 2 |
|
Bolacha stream/RS | 54 | 54m/sm | 108 | 6 | term. long arm | - | - | - | 2 |
Paraná river/AR | 54 | 54m/sm | 108 | - | term. long arm | - | - | Inters./term. | 11 | |
Saco da Alemoa river/RS | 54 | 54m/sm + B | 108 | 5 | term. long arm | 2 | - | Peric./term. | 18, 19 | |
Capivara stream/RS | 54 | 54m/sm + B | 108 | 5 | term. long arm | 2 | - | Peric./term. | 18, 19 | |
Gasômetro/RS | 54 | 54m/sm + B | 108 | 5 | term. long arm | 2 | - | Peric./term. | 18, 19 | |
Barros lagoon/RS | 54 | 54m/sm + B | 108 | 5 | term. long arm | 2 | 2/peric. short arm | Peric./term. | 18, 19 | |
Quadros lagoon/RS | 54 | 54m/sm + B | 108 | 5 | term. long arm | 2 | - | Peric./term. | 18, 19 | |
|
A.E.S UFRGS dam/RS | 54 | 54m/sm + B | 108 | 8 | term. long arm | 2 | 2/peric. short arm | Peric./term. | 18, 19 |
|
Negro and Solimões river/AM | 102 | 2m + 2sm + 98a | 106 | 5 | term. long arm | - | - | Peric./inters/term. | 4 |
|
Negro and Solimões river/AM | 56 | 52m + 2sm + 2st | 112 | 25 | term. long arm | - | - | Peric./term. | 4 |
|
Negro and Solimões river/AM | 54 | 42m + 12sm | 108 | 25 | term. short arm | - | - | Peric. | 4 |
|
Paraná river/AR | 102 | 14m/sm + 88a | 116 | - | term. long arm | - | - | Centr. | 11 |
|
Araguaia river/MT | 54 | 44m + 10sm | 108 | 17 | term. short arm | - | - | Peric. | 16 |
|
Miranda river/MS | 54 | 42m + 12sm | 108 | 20 | term. short arm | - | - | Peric. | 7 |
Paraná river/AR | 54 | 54m/sm | 108 | - | inters. long arm | - | - | Centr./term. | 11 | |
|
Negro and Solimões river/AM | 54 | 42m + 12sm | 108 | 9 | term. long arm | - | - | - | 3 |
|
Araguaia river/GO | 54 | 42m + 12sm | 108 | 2, 23 | term. long arm | - | - | Peric./term. | 16 |
|
Forquetinha river/RS | 54 | 54m/sm + B | 108 | 3 | term. long arm | 4 | - | Peric./term. | 18, 19 |
|
Miranda river/MS | 54 | 48m + 6sm | 108 | 17 | term. short arm | - | - | Centr./term. | 7 |
Paraná river/AR | 54 | 54m/sm | 108 | 15 | term. long arm | - | - | Centr./inters./term. | 11 | |
|
Paraguai river/MS | 54 | 54m/sm | 108 | 2 | inters. long arm | - | - | - | 2 |
Paraná river/AR | 54 | 54m/sm | 108 | 2 | term. long arm | - | - | Centr./inters/term. | 11 | |
|
São Francisco river/SP | 54 | 54m/sm | 108 | 25 | term. short arm | - | - | - | 2 |
|
Araguaia river/MT | 54 | 38m + 16sm | 108 | - | term. long arm | - | - | Peric. | 16 |
|
São Francisco river/AC | 54 | 54m/sm | 108 | 24 | term. short arm | - | - | Peric./inters/term. | 9 |
|
Mogi-Guaçu river/SP | 54 | 54m/sm | 108 | 25 | term. short arm | - | - | - | 2 |
Passa-Cinco river/SP | 54 | 54m/sm | 108 | 25 | term. short arm | - | - | - | 2 | |
Paranapanema river/SP | 54 | 54m/sm + B | 108 | - | - | - | - | Peric. | 5 | |
Reserva Jurumirim/SP | 54 | 54m/sm + B | 108 | - | - | - | - | Peric. | 5 | |
Paranapanema river/SP | 54 | 54m/sm | 108 | 7 | term. short arm | 2 | 2/peric. short arm | Centr./term. | 12, 14, 17 | |
Tietê river/SP | 54 | 54m/sm | 108 | 7 | term. short arm | 2 | 2/peric. short arm | Centr./term. | 12, 14, 17 | |
Três Bocas stream/PR | 54 | 54m/sm + B | 108 | 7 | term. short arm | 2 | - | Peric./term. | 13, 15 | |
Taquari river/PR | 54 | 54m/sm | 108 | 7 | term. short arm | 2 | - | Peric./term. | 13, 15 | |
Tibagi river/PR | 54 | 54m/sm | 108 | 7 | term. short arm | 2 | - | Peric./term. | 13, 15 | |
Água da Floresta river/PR | 54 | 54m/sm | 108 | 7 | term. short arm | 2 | - | Peric./term. | 13, 15 | |
Cachoeira de Emas/SP | 54 | 54m/sm | 108 | 22 | term. short arm | - | - | Peric./term. | 16 | |
Água dos Patos river/SP | 54 | 54m/sm + B | 108 | 12 | term. short arm | 2 | - | Peric./term. | 18, 19 | |
Três Bocas streams/PR | 54 | 54m/sm + B | 108 | 12 | term. short arm | 2 | 2/peric. short arm | Peric./term. | 18, 19 | |
Pavão stream/PR | 54 | 54m/sm + B | 108 | 12 | term. short arm | 2 | - | Peric./term. | 18, 19 | |
Jacutinga river/PR | 54 | 54m/sm + B | 108 | 12 | term. short arm | 2 | - | Peric./term. | 18, 19 | |
|
Negro and Solimões river/AM | 54 | 48m + 6sm | 108 | 15 | term. short arm | - | - | - | 3 |
Besides the presence of B chromosomes, another striking feature of the
All studied populations of
In many fish groups, including
The results of
The existing literature presents scarce data on fluorochrome staining in the family
NOR heteromorphism in the homologous chromosomes of two individuals of
To explain the presence of larger and smaller 5S rDNA sites,
C-banding analyses did not allow us to characterize and differentiate among the species and/or genera analyzed in this study. However,
The difference in the amount of heterochromatin in
CMA3 fluorochrome staining revealed fluorescent signals in the heterochromatic regions of many chromosomes of the complement, showing that heterochromatin in these species consists mostly of GC base pairs. A chromosomal pair detected in
In
Two hypotheses have been proposed for the origin of B chromosomes in
In conclusion, these data associated with the previously existing studies for the group, show that, although
The authors are grateful to Dra. Lucia Giuliano-Caetano and MSc Juceli Gonzalez Gouveia for the collection of fish samples. This research was supported by a grant from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and received permission from Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA) to collect fish specimens.