Mapping the distribution of the telomeric sequence (T2AG3)n in the Macropodoidea (Marsupialia) by fluorescence in situ hybridization. II. The ancestral 2n = 22 macropodid karyotypeMetcalfe C.J.a, b · Eldridge M.D.B.b · Johnston P.G.b
aEquipe ATIP Génome, Développement et Evolution, Laboratoire Evolution, Génomes et Spéciation, Centre National de la Recherche Scientifique, Gif-sur-Yvette (France) bDepartment of Biological Sciences, Macquarie University, Sydney (Australia)
In marsupial karyotypes with little heterochromatin, the telomeric sequence (T2AG3)n, is involved in chromosome rearrangements. Here we compare the distribution of the (T2AG3)n sequence in chromosomes recently derived by fusions and other rearrangements (7–0.5 MYBP) with its distribution in chromosomes derived earlier (24–9 MYBP). We have previously shown that the (T2AG3)n sequence is consistently retained during chromosome rearrangements that are recent (7–0.5 MYBP). We suggest that in less recent rearrangements (24–9 MYBP) the pattern observed is initial retention followed by loss or amplification. We also suggest that the presence of interstitial (T2AG3)n sequence is related to the evolutionary status of single chromosomes rather than entire karyotypes.
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Equipe ATIP Génome, Développement et Evolution
Laboratoire Evolution, Génomes et Spéciation
Centre National de la Recherche Scientifique, Gif-sur-Yvette (France)
telephone +33 01 69 82 37 33; fax +33 01 69 82 37 36
C.J.M and M.D.B.E were supported by grants from the Australian Research Council and Macquarie University. This research was funded by the Australian Research Council and Macquarie University.
Manuscript received: 19 June 2006
Accepted in revised form for publication by M. Schmid,: 12 October 2006.
Number of Print Pages : 6
Number of Figures : 3, Number of Tables : 1, Number of References : 38
Cytogenetic and Genome Research
Vol. 116, No. 3, Year 2007 (Cover Date: February 2007)
Journal Editor: Schmid, M. (Würzburg)
ISSN: 1424–8581 (print), 1424–859X (Online)
For additional information: http://www.karger.com/CGR