Türkiye’deki Toros yer sincabı, Spermophilus taurensis Gunduz et al., 2007 (Mammlia: Rodentia)’in kromozomlarındaki heterokromatin dağılımı ve nükleolar organizatör bölgeler (NORs)

Türkiye’deki Toros yer sincabında C-heterokromatin blokların ve nükleolar organizatör bölgelerin dağılımları çalışıldı. Spermophilus taurensis’in karyotipi 40 kromozomdan oluşmuş, temel kromozom kol sayısı (NF) 80 ve otozomal kromozom kol sayısı (NFa) 76’dır. Y kromozomunun tamamı heterokromatinden oluşmuşken, otozomlarının tamamı ve X kromozom perisentromerik heterokromatine sahiptir. NOR’lar 2 çift submetasentrik ve 2 çift subtelosentrik kromozomların kısa kolunun terminal bölgesinde gözlendi. NOR’ların tamamı benzer şekilde ve orta büyüklüktedir. S. taurensis düşük kromozom sayısı, C-pozitif Y kromozomu ve NOR’ların lokalizasyonu ve sayısı açısından S. xanthoprymnus’dan farklıdır. Ayrıca onun Y kromozomunun heterokromatin özelliğinin S. citellus’a benzediği belirlenmiştir.

Anahtar Kelimeler:

Spermophilus taurensis, C-band, NOR lokalizasyonu, Türkiye

Heterochromatin distribution and nucleolar organizer regions (NORs) in chromosomes of the Taurus ground squirrel, Spermophilus taurensis Gunduz et al., 2007 (Mammalia: Rodentia), in Turkey

The distribution of C-heterochromatin blocks and nucleolar organizer regions (NORs) in the Taurus ground squirrel from Turkey was studied. The karyotype of Spermophilus taurensis comprised 40 chromosomes, the fundamental chromosome number (NF) was 80, and there were 76 autosomal arms (NFa). All autosomes and the X chromosome had pericentromeric C-heterochromatin, whereas the Y chromosome appeared to be entirely heterochromatic. NORs were observed in the terminal regions of the short arm of 2 pairs of submetacentric and 2 pairs of subtelocentric chromosomes. All the NORs were homomorphic and of medium size. The S. taurensis karyotype differs from that of S. xanthoprymnus by a low diploid number, by a C-positive Y chromosome, and by the number and localization of NORs. It was also determined that its Y chromosome resembles that of S. citellus, in terms of its heterochromatic nature.

Keywords:

Key words: Spermophilus taurensis, C-banding, NOR localization, Turkey,

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