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1.
Teoman Kankılıç Perinçek Seçkinozan Şeker Tolga Kankılıç Kubilay Toyran Jan Zima 《Zoology in the Middle East.》2017,63(3):181-188
A new karyotype for blind mole rats was recorded in Tunceli province in Eastern Turkey. The karyotype contained 44 chromosomes, including 13 biarmed pairs, 7 acrocentric pairs, and one heteromorphic pair with a submetacentric and an acrocentric homologue in the autosomal complement (FNa=69). The X chromosome was submetacentric and the Y chromosome medium-sized subtelocentric (FN=73). Distinct dark centromeric C-bands were observed on most of the biarmed and three pairs of the acrocentric autosomes. The NORs were detected on short arms of three subtelocentric pairs and one acrocentric pair of autosomes. The diploid number of chromosomes and the karyotype characteristics observed are obviously unique among hitherto studied populations of blind mole rats and the complement can be evaluated as a new chromosome race of Nannospalax xanthodon. The distribution ranges of individual chromosome races of the species recorded in Eastern Anatolia are revised and possible interracial hybridization is discussed in respect of the finding of a new race. 相似文献
2.
本文报道了云南8种树桂的染色体组型,并对目前所已知的树蛙种类的染色体组型进行了比较。锯腿小树蛙Philautuscavirostris(Guenther)的2n=26,5对大染色体和8对小染色体,9M+4SM,NF=52,No.7长臂近着丝粒处和No.8短臂端部备有一个次缢痕;白颊小树蛙Phi.palpebralisSmith的2n=26,5对人染色体和8对小染色体,8M+5SM,NF=52,No.6短臂近着丝粒处有一个次缢痕。白颌大树蛙Rha.maximusGuenther的2n=26,5对大染色体和8对小染色体,9M+4SM,NF=52;棕褶树蛙Rha.feaeBoulenger的2n=26,5对大染色体和8对小染色体,9M+4SM,NF=52;黑蹼树蛙Rha.reinwardtii(Boie)的2n=26,5对大染色体和8对小染色体,9M+4SM,NF=52,Mo.1短臂近着丝粒处有一个次缢痕;红蹼树蛙Rha.rhodopusLiuetHu的2n=26,5对大染色体,1对中染色体和7对小染色体,9M+4SM,NF=52;斑腿泛树蛙Polypedatesmegacephalus的2n=26,5对大染色体 相似文献
3.
以2份角堇与4份大花三色堇自交系为试验材料,采用染色体常规压片方法,观察和分析了它们的细胞染色体数目、相对长度、平均臂比等核型指标,以明确两种植物细胞学特点,为分类以及育种提供理论依据。结果表明:(1)2份角堇自交系染色体数目均为2n=2x=26,染色体基数为x=13,染色体核型公式分别为2n=2x=26=8m+12sm+6st、2n=2x=26=4m+16sm+6st,核型不对称系数为67.20%~70.10%,核型分类均属于3B。(2)4份大花三色堇自交系均为四倍体,其中2份(EYO-1-2-1-4、DSRFY-1-1-2)染色体数目为44,核型公式为2n=4x=44=4m+16sm+6st、2n=4x=44=16m+24sm+4st;2份(G10-1-3-1-4、XXL-YB-1-1-1-1)染色体数目为48,核型公式分别为2n=4x=48=8m+20sm+20st、2n=4x=48=4m+36sm+8st,核型不对称系数为66.74%~71.77%,核型分类属于2B、3B。 相似文献
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5.
采用常规压片法研究了菊科(Compositae)假福王草属(Paraprenanthes Chang ex Shih)、翅果菊属(PterocypselaShih)和紫菊属(Notoseris Shih)3属5种植物的染色体数目及核型,其中林生假福王草(Paraprenanthes diversifolia)的核型为首次报道。结果表明,该5种植物的染色体数目均为2n=18,核型结果分别为林生假福王草2n=8m+10sm(2SAT);翅果菊(Pterocypsela indica)2n=4m+10sm+4st;光苞紫菊(Notoseris macilenta)2n=10m+8sm(2SC);三花紫菊(Notoseris triflora)2n=10m(2SAT)+8sm;南川紫菊(Notoseris porphyrolepis)2n=12m(2SC)+6sm;林生假福王草和紫菊属4个种的核型为"2A"型,翅果菊的核型为"3A"型。 相似文献
6.
A new natural allotriploid,Lycoris × hubeiensis hybr. nov. (Amaryllidaceae), identified by morphological,karyological and molecular data 下载免费PDF全文
A new natural hybrid, Lycoris × hubeiensis K. Liu, is confirmed and described based on morphological, karyological and molecular data. The new natural hybrid displays remarkable morphological differences relative to the putative parents L. radiata (2n = 22 = 22A) and L. aurea (2n = 14 = 8m + 6T), and has a karyotype of 3n = 29 = 4m + 22A + 3T. Two chloroplast intergenic regions of ndhF‐rpl32R and rpl32F‐trnL were sequenced with three haplotypes found in the three taxa. The putative hybrid and L. radiata shared the same haplotype (H1), while L. aurea had two other haplotypes (H2 and H3). Combined with the morphological, karyological and molecular data, we conclude that the hybrid is an allotriploid with L. radiata being the maternal parent offering an unreduced gamete and L. aurea being the male parent. 相似文献
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8.
T. M. Grinchuk K. M. Ivantsov L. L. Alekseenko I. V. Kozhukharova A. M. Zaichik N. S. Petrov V. M. Mikhailov B. V. Popov 《Cell and Tissue Biology》2009,3(1):29-34
We established and characterized a murine mesenchymal stem cell line from the bone marrow of a transgenic C57BL mouse that ubiquitously expressed green fluorescent protein (GFP). Immunostaining revealed the presence of several markers common for mesenchymal stem cells (MSCs). The cells expressed specific fibroblast proteins, such as smooth muscle actin, which is localized in stress fibrils, and vimentin, a major protein of intermediate filaments in connective tissue cells. These proteins are responsible for the ability to differentiate into adipocytes or osteoblasts under appropriate conditions. The MSC karyotype was unstable. At the 6th passage cells, were aneuploid and genetically heterogeneous. The number of chromosomes ranged from near 2n to 8n. 80% of cells had chromosome numbers between 50 and 85 without a well-defined modal class. Differential G-staining of metaphase spreads showed variability in the copy numbers of individual chromosomes and presence of random chromosome rearrangements, such as ectopic associations of nonhomologous chromosomes. All cells analyzed contained a single dicentric marker chromosome. Some cells also had mini-chromosomes regarded as indicators of gene amplification. We suppose that the karyotypic instability of MSCs that express GFP is provoked by the insertion of foreign GFP transgenes into the murine genome. These cells could be useful for the study of genomic alterations during the spontaneous oncogenic transformation of stem cells. 相似文献
9.
赤链蛇染色体组型、C型和Ag—NORs的研究 总被引:1,自引:0,他引:1
以骨髓细胞为材料研究赤链蛇的染色体,结果表明该物种2n=46,由8对大型的和15对微小的染色体组成,AF=50。性染色体的大小介于3号和4号之间,为ZW;8大型染色体均显示着丝粒C带,1-6号还显示浅染端粒C带。W染色体为整条C带阳性,该物种一对NOR位于7号染色体近着丝粒区。不同地理分布群赤链蛇核型可能经历过Z与W染色体不等交换。 相似文献
10.
D. Araujo C. A. Rheims A. D. Brescovit D. M. Cella 《Journal of Zoological Systematics and Evolutionary Research》2008,46(2):89-95
Genus Scytodes includes most species of the spider family Scytodidae. Until now, 187 species of the genus have been described. In spite of this great diversity, only three Scytodes species were karyotyped so far. The present paper provides for the first time karyotype analysis of two synanthropic species, Scytodes fusca and Scytodes itapevi. Furthermore, new data on karyotype of Scytodes globula are also provided using conventional and differential cytogenetical procedures. The diploid number in the genus Scytodes varied considerably, namely from 2n = 13 to 2n = 31. The diploid number found in S. globula (2n♂ = 13) is the lowest in haplogyne spiders with monocentric chromosomes. Except S. globula, this number has been found only in one haplogyne spider with monocentric chromosomes, namely Ochyrocera sp. (Ochyroceratidae). On the contrary, the diploid number of S. fusca (2n♂ = 31) is one of the highest diploid numbers recorded in haplogyne spiders. The degree of intrageneric variation found in the genus Scytodes is the highest recorded in araneomorph spiders with monocentric chromosomes so far. Some karyotype characteristics (diploid number, chromosome morphology, total chromosome length, and distribution of constitutive heterochromatin) allowed us to postulate a close relationship between S. globula and S. itapevi. According to the karyotype data, S. fusca is not closely related to these two species. This conclusion corroborates a recent taxonomic work that grouped S. globula, S. itapevi, and other four Scytodes species in the ‘globula group’. 相似文献