Chromosomal and Synaptonemal Complex Analysis of Robertsonian Polymorphisms in Akodon dolores and Akodon molinae (Rodentia, Cricetidae) and their Hybrids.

Wittouck, P.; Senn, E. Pinna; Soñez, Carlos Alberto; Provensal, M. Cecilia; Polop, Jaime; Lisanti, José A.

doi:10.1508/cytologia.60.93

Cited by 10 publications

(11 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A. azarae and A. boliviensis belong to a group of species whose populations include a considerable proportion of fertile XY females (reviewed in Bianchi, 2002). A. dolores, on the other hand, shows a remarkable Robertsonian polymorphism affecting biarmed pairs 2 to 5, and a more complex polymorphism of pair 1 that implies pericentric inversions and loss of heterochromatin (Bianchi et al, 1979;Wittouck et al, 1995).…”

confidence: 99%

Chromosomal localization of telomeric sequences in three species of <i>Akodon</i> (Rodentia, Sigmodontinae)

Viera

Ortiz²,

Pinna-Senn³

et al. 2004

Cytogenet Genome Res

View full text Add to dashboard Cite

The distribution of the vertebrate telomeric sequence T₂AG₃ in three species of the rodent genus Akodon was examined by FISH with a peptide nucleic acid probe. In addition to the expected telomeric hybridization, non-telomeric signals were observed in the three species. In A. dolores, centromeric signals were visible in two of the four biarmed autosome pairs featuring Robertsonian polymorphism, indicating the retention of at least part of the telomeric sequences during the fusion process, and an interstitial signal of lower intensity was observed in the short arm of another. In A. boliviensis, a strong signal was observed near the centromeric end of the first chromosome pair. The first pair of A. azarae (homologous to the first pair of A. boliviensis) showed a similar but markedly amplified signal, and a subcentromeric signal in the X chromosome corresponding to a heterochromatic region; additionally, interstitial signals of lower intensity were present in one to four chromosomes in the majority of cells examined.

show abstract

confidence: 99%

Chromosomal localization of telomeric sequences in three species of <i>Akodon</i> (Rodentia, Sigmodontinae)

Viera

Ortiz²,

Pinna-Senn³

et al. 2004

Cytogenet Genome Res

View full text Add to dashboard Cite

show abstract

“…In Akodon dolores, with Rb polymorphisms of pairs 2 to 5 and another of pair 1 that resembles that of A. cursor (Bianchi et al 1979, Wittouck et al 1995, centromeric ITS are observed only in pairs 4 and 5 (Viera et al 2004). Similarly, 2 cytotypes of the Oryzomys subflavus complex, related by 4 Rb rearrangements, show ITS in only 2 of the 4 biarmed pairs (Andrades-Miranda et al 2002).…”

mentioning

confidence: 99%

Localization of Telomeric Sequences in the Chromosomes of Three Species of Calomys (Rodentia, Sigmodontinae)

et al. 2007

View full text Add to dashboard Cite

SummaryThe distribution of telomeric sequences in 3 species of the phyllotine genus Calomys, whose members are distributed through an extensive area of South America, were analyzed by FISH with a PNA probe. C. musculinus, with a highly reordered karyotype with respect to other species of the genus, and C. venustus only showed fluorescent signals in a telomeric position. C. laucha, on the other hand, presented in addition a remarkable set of internal telomeric signals (ITS). ITS were seen constantly in the centromeric regions of biarmed pairs 1 and 2 and the X chromosome of this species, being the latter signal formed by 2 separated marks. On the basis of previous karyotypic information, these constant signals are interpreted as resulting from rearrangements occurred during karyotypic evolution. Additional signals of generally lower intensity were observed with different frequencies in up to 6 subterminal chromosomes of this species.

show abstract

“…However, the taxonomy and systematics of the genus remain unresolved, mainly due to the great similarity between its species, and thus a comprehensive revision of the genus would be welcome (Diaz et al 1999). This genus is cytogenetically very interesting because of its systematic complexity, its considerable karyotypic diversity (2n =10-52), but, paradoxically, karyotypically indistinguishable species, the existence of intraspecific variation affecting the autosomes and the sex chromosomes, and the presence of species with fertile XY-females (Bianchi et al 1971, 1973, 1979a, b, 1989, 1993, Fagundes et al 1998, Fernandez-Donoso et al 2001, Gallardo 1982, Ortiz et al 1998, Silva and Yonenaga-Yassuda 1998, Vitullo et al 1986, Wittouck et al 1995.…”

mentioning

confidence: 99%

“…azarae is one of the species of Akodon in whose populations fertile XY females are present (Bianchi and Contreras 1967, Bianchi et al 1971, 1989, 1993, Espinosa and Vitullo 1996, Ortiz et al 1998, Solari et al 1989. A. molinae and A. dolores share an interesting polymorphism of their first chromosome pair, which can appear as a submetacentric or as 2 subterminal chromosomes, whilst A. dolores exclusively shows Robertsonian polymorphisms of pairs 2 to 5 (Bianchi et al 1973, 1979a, b, Fernandez-Donoso et al 2001, Wittouck et al 1995. These 2 morphologically and genetically very similar species (Apfelbaum andBlanco 1984, Wittouck et al 1995) share the Gbanding patterns of their autosomal arms and of the sex chromosome pair and produce fertile hybrids, at least in the laboratory (Bianchi et al 1979b, Merani et al 1978, Roldan et al 1984, Wittouck et al 1995.…”

mentioning

confidence: 99%

Characterization of the Chromosomes of Three Species of Akodon (Rodentia, Sigmodontinae) by Means of Fluorochromes Highly Selective for DNA Base Composition.

et al. 2001

View full text Add to dashboard Cite

Summary Akodon is the richest Sigmodontine genus in terms of number of species. This article analyzes the chromosomal banding produced in A. azarae, A. molinae and A. dolores by the fluorochromes 4,6-diamidino-2-phenylindole (DAPI) and chromomycin A3 (CMA), counterstained in some cases with distamycin A (DA). A. azarae populations have fertile XY females, and A. molinae and A. dolores, a pair of closely related species, show Robertsonian polymorphisms. In the 3 species, as generally observed in mammals, DAPI-treated chromosomes presented a G/Q-like fluorescent pattern, and DA-CMA treatment gave R-type banding. The constitutive heterochromatin of A. azarae, comprising the centric regions of the autosomes (excepting the small metacentric), the Ychromosome, and several bands of the X amounting to almost 38% of its length, fluoresced with DAPI and appeared negative with DA-CMA, indicating the relative AT-richness of their repetitive components. In A. molinae and A. dolores, no characteristic fluorescence was noticed in the small heterochromatic regions of the autosomes. The heterochromatic Y of these species could be differentiated into a centric portion (approximately one third of the chromosome) that fluoresced with DA-CMA, and was therefore relatively GC-rich, and a distal portion that fluoresced brightly with DAPI, which was thus relatively AT-rich; the small centric band of the X fluoresced with CMA. The response of the gonosomal centric regions indicates that these chromosomes associate by their centromeric ends in diakinesis-metaphase I. These observations confirm the utility of fluorochromes that are highly selective for DNA base pair composition in cytogenetic studies, and further our understanding of the chromosomal evolution in this genus.

show abstract

Chromosomal and Synaptonemal Complex Analysis of Robertsonian Polymorphisms in Akodon dolores and Akodon molinae (Rodentia, Cricetidae) and their Hybrids.

Cited by 10 publications

References 32 publications

Chromosomal localization of telomeric sequences in three species of <i>Akodon</i> (Rodentia, Sigmodontinae)

Chromosomal localization of telomeric sequences in three species of <i>Akodon</i> (Rodentia, Sigmodontinae)

Localization of Telomeric Sequences in the Chromosomes of Three Species of Calomys (Rodentia, Sigmodontinae)

Characterization of the Chromosomes of Three Species of Akodon (Rodentia, Sigmodontinae) by Means of Fluorochromes Highly Selective for DNA Base Composition.

Contact Info

Product

Resources

About