Variation in C-heterochromatin and NOR distribution among chromosomal races of mole rats (Spalacidae) from Central Anatolia, Turkey

Abstract

a b s t r a c tIn this study, the 2n = 40, 58, 60 chromosome races of mole rats of the Nannospalax nehringi superspecies from the Konya province in Turkey were investigated. Conventional chromosome staining, Ag-NOR staining and C-banding analysis was carried out on 25 specimens of mole rats from 13 localities. The description of conventional karyotypes revealed the detailed pattern of geographic distribution of individual races of mole rats in Central Anatolia. The C-positive regions were localized in centromeric areas, and/or in short arms of submetacentric and subtelocentric autosomes. In the 2n =40 race, C-heterochromatin regions were found in whole short arms of four biarmed autosomal pairs whereas C-heterochromatin was localized in pericentromeric areas of biarmed and acrocentric autosomes in the karyotypes of the other races. Autosomal pairs heteromorphic possibly due to deletion/addition of heterochromatin and euchromatin material in short arms were recorded in some populations of both the 2n =58 and 60 chromosome races. The distribution of nucleolar organizer regions (NORs) was described for the first time in the 2n = 40 and 58 races. The NORs were localized in four pairs of biarmed autosomes in all the studied chromosomal races in distal heterochromatic and euchromatic areas of the short arms. The results demonstrate the considerable extent of variation in C-heterochromatin and NORs distribution in karyotypes of mole rats from Anatolia.

Heterochromatin distribution and localization of NORs in the 2n = 48cytotypes of Nannospalax xanthodon and N. ehrenbergi

“…The fundamental number of autosomal arms (NFa) and the number of all chromosomal arms in the female complement (NF) were calculated. We followed the arrangement of chromosomes in the karyotype applied in some previous papers (Ivanitskaya et al, 1997(Ivanitskaya et al, , 2008Arslan et al, 2011). …”

Chromosomal evolution of the Genus Nannospalax (Palmer 1903) (Rodentia, Muridae) from western Turkey

“…Currently more than 30 chromosomal races have been determined in Turkish blind mole rats but there is still doubt about the taxonomy of this taxon (Nevo et al, 1994;Sözen et al, 1998aSözen et al, , 1998bSözen et al, , 1999Sözen et al, , 2000aSözen et al, , 2000bSözen et al, , 2006aSözen et al, , 2006bSözen et al, , 2011Sözen, 2004;Matur and Sözen, 2005;Kankiliç et al, 2007;Ivanitskaya et al, 2008;Arslan et al, 2011). Kandemir et al (2012) discussed the taxonomic name problem of blind mole rats and so here we will follow Kandemir et al (2012).…”

“…They assumed that ancestral karyotype diverged into the 2n = 60W and R chromosomal races, and independent translocations of short arms of some chromosomes caused this differentiation. Arslan et al (2011) studied variation of C-and AgNOR-banding of 3 chromosomal races (2n = 40, 58, and 60) of N. xanthodon from southern Anatolia. They found differentiation among the chromosomal races.…”

Karyological studies of the 2n= 60 cytotype ofNannospalax nehringifrom Central Anatolia

“…Both Sözen et al (2011) and Matur et al (2011) decided to use N. nehringi instead of S. leucodon. However, Arslan and Bölükbaş (2010), , Arslan et al (2011a) and Arslan et al (2011b) adopted both N. nehringi and N. xanthodon for the mole rats distributed in Central Anatolia.…”