Metcalfe C J, Eldridge M D B, Johnston P G
Equipe ATIP Génome, Développement et Evolution, Laboratoire Evolution, Génomes et Spéciation, Centre National de la Recherche Scientifique, Gif-sur-Yvette, France.
Cytogenet Genome Res. 2007;116(3):212-7. doi: 10.1159/000098189.
In marsupial karyotypes with little heterochromatin, the telomeric sequence (T(2)AG(3))(n), is involved in chromosome rearrangements. Here we compare the distribution of the (T(2)AG(3))(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 (T(2)AG(3))(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 (T(2)AG(3))(n) sequence is related to the evolutionary status of single chromosomes rather than entire karyotypes.
在异染色质较少的有袋类动物核型中，端粒序列（T(2)AG(3)）(n)参与染色体重排。在此，我们比较了近期通过融合及其他重排产生的染色体（7 - 0.5百万年前）中（T(2)AG(3)）(n)序列的分布与其在早期产生的染色体（24 - 9百万年前）中的分布情况。我们之前已经表明，在近期（7 - 0.5百万年前）的染色体重排过程中，（T(2)AG(3)）(n)序列一直得以保留。我们认为，在更早的重排（24 - 9百万年前）中，观察到的模式是最初保留，随后丢失或扩增。我们还认为，居间（T(2)AG(3)）(n)序列的存在与单个染色体而非整个核型的进化状态相关。
