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Visualization of nucleolar organizer regions in sloths (Bradypus variegatus and Scaeopus torquatus)

Beatriz Goldschmidt^I; José Carlos Cabral de Almeida^II; Vera Lucia de Oliveira^III

^IDepartamento de Zootecnia, Faculdade de Veterinária, Universidade Federal Fluminense, Rua Vital Brasil Filho 64, 24230-340 Niterói, RJ, Brasil. Send correspondence to B.G.
^IIUnidade de Citogenética Humana, Instituto de Biofísica Carlos Chagas Filho, UFRJ, Ilha do Fundão, 21910 Rio de Janeiro, RJ, Brasil
^IIIFundação Rio-Zoo, Parque da Quinta da Boa Vista s/n, São Cristovão, 20940-040 Rio de Janeiro, RJ, Brasil

ABSTRACT

The nucleolar organizer regions of sloth chromosomes were studied. In Bradypus variegatus there was an intercalar localization of NORs on pair 25, while in Scaeopus torquatus, they were telomeric, suggesting a fusion mechanism of chromosome evolution.

Keywords: nucleolar organizer; Bradypus variegatus; Scaeopus torquatus.

REFERENCES

Goldschmidt, B. and Almeida, J.C.C. (1993). Cytogenetic studies in sloths (B. variegatus). Rev. Brasil. Genet. 16: 939-948.

Henderson, A.S., Warburton, D. and Atwood, K.C. (1972). Location of ribosomal DNA in the human chromosome complement. Proc. Natl. Acad. Sci. 69: 3394-3398.

Henderson, A.S., Warburton, D. and Atwood, K.C. (1974a). Localization of rRNA in the Chimpanzee (Pan troglodytes) chromosome complement. Chromosoma (Berl.) 46: 435-441.

Henderson, A.S., Eichher, E.M., Yu, M.T. and Atwood, K.C. (1974b). The chromosomal location of ribosomal DNA in the mouse. Chromosoma (Berl.) 49: 155-160.

Jorge, W. (1981). Estudo cromossömico de algumas espécies da ordem edentata. Livre-Docência Thesis, Instituto Básico de Biologia Médica e Agrícola, UNESP, Botucatu, SP, Brasil.

Jorge, W. and Pinder, L. (1990). Chromosome study on the maned sloth Bradypus torquatus (Bradipodidae, Xenarthra). Cytobios 62: 21-25.

Jorge, W., Orsi-Souza, M.T. and Best, R. (1985). The somatic chromosomes of Xenarthra. In: The Evolution and Ecology of Armadillos, Sloths and Vermlinguas (Montgomery, G.G., ed.).

Smithsonian Institution Press, Washington and London, pp. 451.

Kopp, E.B., Mayr, B., Czaker, R. and Schleger, W. (1981). Nucleolus organizer regions in the chromosomes of the domestic horse. J. Herod. 72: 357-358.

Moorhead, P.S., Nowell, P.C., Mellman, W.J., Battips, D.M. and Hungerford, D.A. (1960). Chromosome preparation of leucocytes in human peripheral blood. Exp. Cell Res. 20: 613-616.

Muerer-Orlando, M., Llerena Jr., J., McGuire, M., Zahed, L., Crolla, J., Bobrow, M. and Sheridan, R. (1988). Chromosome banding in direct preparations of chorionic villi. Prenatal Diagnosis 8: 461-469.

Pardue, M.L. and Hsu, T.C. (1975). Locations of 18S and 28S ribosomal genes in the chromosomes of the Indian muntjac. J. Cell Biol. 64: 251-254.

Wetzel, R.M. and Avila-Pires, F.D. (1980). Identification and distribution of the recent sloths of Brazil (Edentata). Rev. Brasil. Biol. 40: 831-836.