Heterochromatin

Cytogenetic description of Ancistrus abilhoai (Siluriformes: Loricariidae) from Iguaçu River basin, southern Brazil

M. O. Ribeiro, Noleto, R. B., Lorscheider, C. A., Porto, F. E., Prizon, A. C., Zawadzki, C. H., Oliveira, L. C., and Castro, A. L. B. Portela, “Cytogenetic description of Ancistrus abilhoai (Siluriformes: Loricariidae) from Iguaçu River basin, southern Brazil”, vol. 14, pp. 4051-4057, 2015.

The Iguaçu River basin is a tributary to the upper Paraná River in southern Brazil, and is considered an important aquatic ecoregion that, although having few species of fish, 51-71% of these are apparently endemic. Ancistrus abilhoai is one of three recently described species for this basin and is currently considered endemic to the basin.

Entoepidemiology of Chagas disease in the Western region of the State of São Paulo from 2004 to 2008, and cytogenetic analysis in Rhodnius neglectus (Hemiptera, Triatominae)

K. C. C. Alevi, Rodas, L. A. C., Tartarotti, E., Azeredo-Oliveira, M. T. V., and Guirado, M. M., “Entoepidemiology of Chagas disease in the Western region of the State of São Paulo from 2004 to 2008, and cytogenetic analysis in Rhodnius neglectus (Hemiptera, Triatominae)”, vol. 14, pp. 5775-5784, 2015.

To complement the epidemiological data and assist in the prophylaxis of Chagas disease in the State of São Paulo, we examined entomological lifting conducted in 40 municipalities of the Western region of the state from 2004 to 2008, highlighted the main vector species in this region, and reanalyzed the cytogenetic characteristics of Rhodnius neglectus from 3 different Brazilian states (Formoso/GO, Frutal/MG, Guaíra/SP, and Pitangueiras/SP). The municipalities of Castilho and Santo Antônio do Acaranguá registered the highest relative amounts of notifications.

Physical mapping of 18S rDNA and heterochromatin in species of family Lygaeidae (Hemiptera: Heteroptera)

V. B. Bardella, Sampaio, T. R., Venturelli, N. B., Dias, A. L., Giuliano-Caetano, L., Fernandes, J. A. M., and da Rosa, R., “Physical mapping of 18S rDNA and heterochromatin in species of family Lygaeidae (Hemiptera: Heteroptera)”, vol. 13, pp. 2186-2199, 2014.

Analyses conducted using repetitive DNAs have contributed to better understanding the chromosome structure and evolution of several species of insects. There are few data on the organization, localization, and evolutionary behavior of repetitive DNA in the family Lygaeidae, especially in Brazilian species.

Population divergence and peculiar karyoevolutionary trends in the loricariid fish Hypostomus aff. unae from northeastern Brazil

J. A. Bitencourt, Affonso, P. R. A. M., Giuliano-Caetano, L., Carneiro, P. L. S., and Dias, A. L., “Population divergence and peculiar karyoevolutionary trends in the loricariid fish Hypostomus aff. unae from northeastern Brazil”, vol. 11, pp. 933-943, 2012.

Loricariidae (Siluriformes, Hypostominae) is one of the most diverse catfish families. In spite of the wide distribution of loricariids in South America, cytogenetic reports are available for only a few species, mostly from southern and southeastern Brazil. We made the first chromosomal analysis of Hypostomus aff. unae from the Contas River basin in northeastern Brazil.

Sex chromosome differentiation in Belostoma (Insecta: Heteroptera: Belostomatidae)

V. B. Bardella, Dias, A. L., Giuliano-Caetano, L., Ribeiro, J. R. I., and da Rosa, R., “Sex chromosome differentiation in Belostoma (Insecta: Heteroptera: Belostomatidae)”, vol. 11, pp. 2476-2486, 2012.

Belostoma, a genus of the family Belostomatidae, includes species of great ecological importance as biocontrol agents. Few species of these species have been the subject of cytogenetic analyses. Karyotypic evolution in this genus involves agmatoploidy and simploidy; there are also different sex chromosome systems. We examined two Belostoma species (B. dilatatum and B. candidulum) collected from the Paranapanema River Basin (Brazil). Mitotic and meiotic analysis revealed 2n(♂) = 26 + X1X2X3Y for B.

Cytogenetics of the darkling beetles Zophobas aff. confusus and Nyctobates gigas (Coleoptera, Tenebrionidae)

A. C. Lira-Neto, Silva, G. M., Moura, R. C., and Souza, M. J., “Cytogenetics of the darkling beetles Zophobas aff. confusus and Nyctobates gigas (Coleoptera, Tenebrionidae)”, vol. 11, pp. 2432-2440, 2012.

Males of Zophobas aff. confusus and Nyctobates gigas (Tenebrionidae) collected in the State of Pernambuco, Brazil, were studied through conventional staining, C-banding, silver nitrate impregnation (AgNO3), and the base specific fluorochromes CMA3 and DAPI. Z. aff. confusus was found to have 2n = 20 (9+Xyp) while N. gigas exhibited 2n = 18 (8+neoXY).

Karyotypic evolution trends in Rhamdia quelen (Siluriformes, Heptapteridae) with considerations about the origin and differentiation of its supernumerary chromosomes

C. Garcia, Oliveira, C., and Almeida-Toledo, L. F., “Karyotypic evolution trends in Rhamdia quelen (Siluriformes, Heptapteridae) with considerations about the origin and differentiation of its supernumerary chromosomes”, vol. 9, pp. 365-384, 2010.

Among catfish species of the genus Rhamdia reported for the Brazilian territory, R. quelen is the most widespread, being found in nearly all hydrographic basins of Brazil. Nowadays, R. quelen is a synonym for at least 47 other species in this genus, its taxonomic status still being controversial. The available cytogenetic reports show a wide variation in the karyotypic macrostructure, with the frequent presence of supernumerary chromosomes. The remarkable cytogenetic variability associated with taxonomic issues in this species indicates that R.

Comparative study of the cytogenetic and molecular characteristics of Triatoma maculata and T. pseudomaculata (Heteroptera, Triatominae)

P. P. Mendonça, “Comparative study of the cytogenetic and molecular characteristics of Triatoma maculata and T. pseudomaculata (Heteroptera, Triatominae)”, vol. 9. pp. 434-434, 2010.

Possible origins of B chromosomes in Rineloricaria pentamaculata (Loricariidae, Siluriformes) from the Paraná River basin

F. E. Porto, Portela-Castro, A. L. B., and Martins-Santos, I. C., “Possible origins of B chromosomes in Rineloricaria pentamaculata (Loricariidae, Siluriformes) from the Paraná River basin”, vol. 9, pp. 1654-1659, 2010.

We made a cytogenetic study of Rineloricaria pentamaculata from the Tauá Stream, in the Pirapó River sub-basin in Paraná State, Brazil, focused on the occurrence and origins of the B chromosomes. The diploid number varied from 2n = 56 to 2n = 59, due to the presence of 0 to 3 B microchromosomes of the acrocentric type, which were observed in 92.3% of the specimens (N = 12). These chromosomes were totally heterochromatic, with the C banding technique, and there were inter- and intraindividual numerical differences.

The role of α-satellite DNA and heterochromatin polymorphism in leukemia patients and illicit drug addicts

A. Movafagh, Mortazavi-Tabatabaei, S. A., and Kolahi, A. A., “The role of α-satellite DNA and heterochromatin polymorphism in leukemia patients and illicit drug addicts”, vol. 10, pp. 3999-4005, 2011.

Heterochromatin is considered to play a role in protecting the genome against mutagens. Changes in the quantity and proportion of different types of satellite DNA could increase genetic susceptibility in individuals with heterochromatic variations; they cause chromosome instability and predispose patients to malignancies. We evaluated the heterochromatin associated with chromosomes in 50 leukemia patients, 93 drug addicts and 93 healthy controls from Tehran, Iran.

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