Fagundes V, Scalzi-Martin J M, Sims K, Hozier J, Yonenaga-Yassuda Y
Departamento de Biologia, Universidade de São Paulo, Brazil.
Cytogenet Cell Genet. 1997;78(3-4):224-8. doi: 10.1159/000134662.
The neotropical rodents Akodon cursor (2n = 14, 15, and 16) and A. montensis (2n = 24 and 25), two closely related and morphologically indistinguishable species, have been compared by G-banding and chromosome painting. In situ hybridization of a biotinylated DOP-PCR product obtained from a microdissected chromosome of A. cursor onto A. montensis chromosomes was performed in combination with localization of telomeric sequences using a (TTAGGG)n oligomer as a FISH probe. The results provide evidence of the complex chromosomal rearrangements suggested by GTG-banding analysis, indicating the origin of one A. cursor autosome from three different A. montensis autosomes. Furthermore, the complete cytogenetic homeology between the A. cursor and A. montensis karyotypes was determined, along with the occurrence of tandem fusions and pericentric inversions and the loss of telomeres, centromeres, and chromosome arms. Evidence for the ancestral origin of the A. cursor karyotype is also provided.
新热带区啮齿动物库氏稻鼠（2n = 14、15和16）和蒙特稻鼠（2n = 24和25）是两个亲缘关系密切且形态上难以区分的物种，已通过G显带和染色体涂染技术进行了比较。将从库氏稻鼠一条显微切割染色体获得的生物素化DOP-PCR产物与以（TTAGGG）n寡聚物作为荧光原位杂交（FISH）探针的端粒序列定位相结合，对蒙特稻鼠染色体进行原位杂交。结果为GTG显带分析所提示的复杂染色体重排提供了证据，表明库氏稻鼠的一条常染色体起源于蒙特稻鼠的三条不同常染色体。此外，还确定了库氏稻鼠和蒙特稻鼠核型之间完全的细胞遗传学同源性，以及串联融合、臂间倒位的发生情况，还有端粒、着丝粒和染色体臂的丢失。同时也提供了库氏稻鼠核型祖先起源的证据。
