Folia Zool. – 58(1): 9–13 (2009)
C-banded karyotype and NORs of the long-eared hedgehog,
Hemiechinus auritus from Turkey
Atilla ARSLAN1*, İrfan ALBAYRAK2, Nahit PAMUKOĞLU2, Tarkan YORULMAZ2 and Kubilay
TOYRAN2
1
Department of Biology, Faculty of Science, Selcuk University, 42031 Konya-Turkey;
e-mail: [email protected]
2
Department of Biology, Faculty of Science and Arts, Kırıkkale University, 71450 Kırıkkale, Turkey
Received 11 September 2007; Accepted 5 January 2009
A b s t r a c t . The karyotype, C-banding, and nucleolar organizer regions (NORs) of six specimens
of Hemiechinus auritus from Turkey were examined. The diploid number of chromosomes was
2n = 48, the fundamental number of chromosome arms FN = 96, and the number of autosomal
arms FNa = 92. Most of the chromosomes possessed centromeric constitutive heterochromatin,
except of the pairs nos. 4, 6, 7, 8, 9, 12, and 17. The X and Y chromosomes appeared to be
euchromatic, and possible geographic variation in their morphology was indicated in comparison
with previously published data. The NORs were located in the terminal regions of the long arms
of four metacentric or submetacentric chromosomes. The localization of the NORs was not
associated with C-positive autosomal regions as in hedgehogs of the genus Erinaceus.
Key words: chromosomal variation, mammals, insectivores
Introduction
The family Erinaceidae comprises six genera and 15 species distributed in Africa, Europe,
and Asia, including certain parts of Indo-Malaysia (W i l s o n & R e e d e r 2005). The
karyotype of Hemiechinus auritus (Gmelin, 1770) was studied by G r o p p et al. (1969)
from Afghanistan, O r l o v (1969) from Daghestan, G r o p p et al. (1969) and D e H o n d t
(1988) from Egypt, B h a t n a g a r & E l - A z a w i (1978) from Iraq, S h a r m a et al.
(1975) and S o b t i & G i l l (1980) from India, Z i m a & K r á l (1984) from the Karakum desert in Turkmenistan, and K e f e l i o ğ l u (1997) and Ç o l a k et al. (1998) from
Turkey. The G-, C-banding and NORs patterns were reported by G r o p p et al. (1969),
G r a p h o d a t s k y et al. (1991), Y a n g et al. (1991), O ’ B r i e n et al. (2006), and Y a n g
et al. (2006). M a n d a h l (1978, 1979) and Z i m a & K r á l (1984) emphasized that the
species belonging to the family Erinaceidae have similar karyotypes but the localization of
C-bands and NORs on chromosomes should be considered in their karyotypical structure,
because their distribution may vary among both the species and populations. In this study,
we aim to examine the karyotype of H. auritus from Turkey, with a special emphasis to the
C-banding pattern and the distribution of nucleolar organizer regions (NORs).
Materials and Methods
The examined total six specimens (2 males, 4 females) of long-eared hedgehogs were
collected from the Urfa (Ceylanpınar) and the central part of the Kilis province in Turkey.
Chromosomal preparations were made using air-drying method from bone marrow (F o r d
* Corresponding author
9
& H a m e r t o n 1956) after short cell cultivation, and conventional Giemsa-staining was
applied. Constitutive heterochromatin and nucleolar organizer regions (NORs) were detected
with C-banding (S u m n e r 1972) and Ag-NOR staining (H o w e l l & B l a c k 1980),
respectively. A total of 10 to 20 slides were prepared from each specimen, and at least 20
well-spread metaphase plates were analysed. Chromosome morphologies were determined
according to Z i m a (1978) by calculating centromeric indices.
Results and Discussion
The karyotype contained 48 chromosomes, the fundamental number of chromosomal arms
was FN = 96, and the number of autosomal arms FNa = 92. All the autosomes and the sex
chromosomes were bi-armed. The karyotype contained one pair of large subtelocentric
autosomes (no. 23), two pairs of very small metacentric autosomes (nos. 21-22), and 20
pairs of metacentric and submetacentric autosomes with gradually decreasing size (nos.
1-20). The X chromosome was a medium-sized metacentric and the Y chromosome was
the smallest bi-armed element of the complement (Fig. 1). The karyotype and chromosome
characteristics of the specimens examined are quite similar to those reported in Afghanistan,
Daghestan, Egypt, Iraq, India, Kara-kum, China and Turkey (G r o p p et al. 1969, O r l o v
1969, B h a t n a g a r & E l - A z a w i 1978, S h a r m a et al. 1975 S o b t i & G i l l 1980,
Z i m a & K r á l 1984, D e H o n d t 1988, Y a n g et al. 1991, 2006, K e f e l i o ğ l u
1997, Ç o l a k et al. 1998). Slightly different chromosome complements of H. auritus were
reported from India (S h a r m a et al. 1975), Iraq (B h a t n a g a r & E l - A z a w i 1978),
and Iran-Zenjan (K a r a t a ş et al. 2007). The karyotypes of hedgehogs from Iraq and India
differed by morphology and size of the sex chromosomes, whereas the specimens from Iran
Fig. 1. Metaphase spread and karyotype of Hemiechinus auritus.
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Fig. 2. Metaphase spread and C-banded karyotype of Hemiechinus auritus.
had a slightly different autosomal set characterized by the presence of dot-like and acrocentric
chromosomes. These differences indicate possible geographic variation in the karyotype of
H. auritus.
The C-banded karyotype is shown in Fig. 2. Most of the autosomes contained a distinct
block of centromeric constitutive heterochromatin, which was not observed in the autosomal
pairs nos. 4, 6, 7, 8, 9, 12, and 17. The chromosome pair no. 21 appeared to be entirely
C-heterochromatic. The X and Y chromosomes were stained C-negatively, and appeared to
be euchromatic.
G r o p p et al. (1969) determined heterochromatin regions in the karyotype of H. auritus
by autoradiography. They observed heterochromatin in centromeric regions of some of the
autosomes and in the sex chromosomes. G r a p h o d a t s k y et al. (1991) and Y a n g et al.
(1991) found a similar C-banding pattern in the autosomes, but the sex chromosomes were
stained C-negatively. M a n d a h l (1978) detected indistinct C-bands in the centromeric
regions of some chromosomes in species of the genus Erinaceus.
By using silver-nitrate staining, NORs were determined in the telomeric region of the
long arm of two pairs of metacentric or submetacentric chromosomes (Fig. 3). Y a n g et
al. (1991) determined active NORs in the terminal and interstitial position on long arms of
3-5 chromosomes. M a n d a h l (1979) observed six NORs in different autosomal pairs of
hedgehogs of the genus Erinaceus. The localization of NORs in H. auritus is not associated
with heterochromatic regions as in the species of the genus Erinaceus.
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Fig. 3. Silver-stained metaphase of Hemiechinus auritus. Arrow indicates the Ag-NOR bearing chromosomes.
Acknowledgements
We thank Prof. Dr Jan Z i m a and two anonymous referees for your valuable comments on an earlier version of
the manuscript.
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