Distribution of constitutive heterochromatin and nucleolar organizer regions (NORs) in Mustela nivalis Linnaeus, 1766 (Carnivora, Mustelidae) in Turkey

Abstract

C- and Ag-NOR banding of the least weasel, Mustela nivalis, from the central and Mediterranean regions of Turkey was examined for the first time in this study. The chromosome set was composed of 18 biarmed and three acrocentric autosome pairs. The X chromosome was a medium-sized submetacentric, while the Y was a small metacentric. A distinct secondary constriction was observed on the juxta centromeric region of the long arm of an autosome that was negatively C-banded. Large heterochromatic C-blocks, stained densely, were detected in six biarmed pairs, while ones stained faintly were recorded in four biarmed autosome pairs. Active NORs were located in the secondary constriction of the acrocentric autosome. The numbers of C-banded autosomes of Turkish specimens were similar to those reported previously from the Palearctic region.