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The karyotypes ofCercopithecus alcogularis andC. mitis, both with 72 chromosomes, are similar but differ in a numer of rearrangements.C. nicitans (2n=70) andC. mitis karyotypes, even though differing in diploid number, appear to be closely related to each other because of several banding features and especially because they may be linked by a derived complex inversion polymorphism. The results show that chromosomal inversion variants can survive speciation. These results do not support recent chromosomal phylogenetic interpretations which were based on the finding of a diploid number of 2n=70 forC. mitis. The results described here emphasize the use of chromosomal characters in the study of the phylogeny and taxonomy ofCercopithecus.  相似文献   

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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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We conducted a 5-month survey on primates, with special attention to Goeldi’s monkey (Callimico goeldii),in the rainforest of northwestern Bolivia. Goeldi’s monkey is one of the least documented of all South American primates, and very little is known about its distribution. We report observations on distribution, abundance, and habitat of Callimico goeldiiand other primates, incidental sightings of other mammals, and preliminary behavioral observations on Callimicoand on two associated callitrichid monkey species: Saguinus fuscicollisand S. labiatus.We found a locality that appears to be particularly suitable for detailed field observations on Callimico on the north bank of the lower Río Tahuamanu. The fieldwork was carried out by A.C.; the analysis of the vocalizations, by T. G.  相似文献   

5.
Leaping to and from vertical trunks is a pattern of locomotor behavior that characterizes the positional repertoire of several prosimian and neotropical primate species. We examined the kinematics of leaping in a group of 6 captive Goeldis monkeys. We introduced a set of 2 wooden, fixed, non-compliant vertical supports in their enclosure and used 2 video cameras set at right angles to document leaping. The supports are 2.5, 6, or 15 cm in diameter and were placed at distances of between 1 and 2 m. We conducted frame-by-frame analyses of 122 leaps. The results indicate that irrespective of distance leaped and the diameter of takeoff and landing substrates, the forelimbs of {Callimico} contacted the landing platform in advance of the hind limbs. Moreover, even when leaping a horizontal distance of 2 m, {Callimico} experienced a downward vertical displacement of only 0.17 m. Several features of the shoulder and forelimb of {Callimico} appear to be associated with enhanced stability at the humeral head and radioulnar joint, and are consistent with the ability to withstand large compressive forces generated when landing on noncompliant substrates. Based on a series of kinematic equations provided by Warren and Crompton (1998a), the mechanical cost of transport in {Callimico} (5.4 m/s–2) is greater than those of prosimian vertical clingers and leapers. However, compared to other callitrichine primates, {Callimico goeldii} is behaviorally and anatomically specialized for leaping between vertical trunks in the lowest layers of the forest understory.  相似文献   

6.
The activity of several families of transposable elements (TEs) in the genome of Fusarium oxysporum represents a potential source of karyotypic instability. We investigated transposon-mediated chromosome rearrangements by analyzing the karyotypes of a set of strains in which transposition events had occurred. We uncovered exceptional electrophoretic karyotype (EK) variability, in both number and size of chromosomal bands. We showed that EK differences result from chromosomal translocations, large deletions, and even more complex rearrangements. We also revealed many duplicated chromosomal regions. By following transposition of two elements and analyzing the distribution of different families of TEs on whole chromosomes, we find (i) no evidence of chromosomal breakages induced by transposition, (ii) a clustering of TEs in some regions, and (iii) a correlation between the high level of chromosomal polymorphism and the concentration of TEs. These results suggest that chromosome length polymorphisms likely result from ectopic recombination between TEs that can serve as substrates for these changes.  相似文献   

7.
匍茎百合(Lilium lankongense)是青藏高原的一个特有百合物种。为了研究其核型特征以及不同居群间的演化关系,该研究采用常规压片法对8个居群的核型进行观察分析。结果表明:(1)8个居群的染色体核型均为3B型,染色体基数为12,核型不对称系数(As.K%)为81.28%~83.53%。(2)结合前人的研究表明,匍茎百合各居群在地理分布上沿着察隅县-茨中村-香格里拉市-木里县一线从西向东迁移、扩散的分布扩张,同时分布于贡山县至香格里拉市一线的居群在地理分布上还存在纬度上的向北和向南迁移、扩散的分布扩张态势。(3)该研究首次发现匍茎百合存在B染色体的情况,其B染色体对适应特殊生境具有重要意义,匍茎百合是一个正处于高度分化过程中的物种。  相似文献   

8.
The Rhesus (Rh) blood group system is the most important blood group system in hemolytic disease of the fetus and newborn (HDFN). In clinical transfusions, the D antigen in the Rh blood group system comes third, behind antigens A and B which from ABO blood group system. Over the past decade, molecular technologies have been used to investigate the RHD allele in different ethnic groups. This review first introduces the basic structure of RhD protein and coding genes, then focuses on D-negative, weak D, partial D, DEL, RhDnull variants reported in the Chinese population. To date, more than 460 RHD variants have been reported around the world, but less than 70 RHD variants have been reported in the Chinese population. Further research is needed to identify more RHD polymorphism and establish criteria for blood detection and transfusion guidelines for RHD variants. Only in this way can we better guarantee the safety of blood transfusion and prevent the occurrence of HDFN. With the accumulation of research and clinical data, we should be clearer which RHD variants are to be regarded as RhD negative and which need to be regarded as RhD positive.  相似文献   

9.
Chromosomal polymorphism has been studied in seven natural populations of Chironomus cingulatus from Western Europe, Western Siberia, and the Republic of Sakha (Yakutia). The banding sequences pool of the species includes 15 banding sequences. Chromosomal polymorphism was revealed in five out of seven chromosomal arms. Arm B is the most polymorphic with four banding sequences. There are three banding sequences in arm A. Arms D, E, and G have two banding sequences. None of the chromosome rearrangements were revealed in arms C and F. The populations of C. cingulatus differ clearly in their number and frequency of banding sequences, which indicates that different gene sequences are adaptive in different populations.  相似文献   

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权有娟  李想  袁飞敏  刘博  陈志国 《广西植物》2021,41(12):1988-1995
为精确地识别藜属植物染色体组的核型特征,该文研究了4种来自青海高原的野生藜属植物(灰绿藜、藜、菊叶香藜及杂配藜)和1种从美国引进的栽培藜麦品种PI614932-HX(3)基于染色体荧光原位杂交(rDNA FISH)的核型。利用5S rDNA和45S rDNA对5种藜属植物有丝分裂中期的染色体进行FISH研究。藜属植物的核型分析结果表明:(1)藜属植物中存在二倍体(2n=2x=18)和四倍体(2n=4x=36)两种倍性,藜麦和灰绿藜为四倍体,其余3种为二倍体。(2)藜麦、灰绿藜、藜、菊叶香藜及杂配藜的核型公式分别为2n=4x=36=34m(2AST)+2sm,2n=4x=36=32m(4AST)+4sm,2n=2x=18=16m(4AST)+2sm,2n=2x=18=18m及2n=2x=18=16m+2sm。(3)染色体由大部分的中部着丝粒染色体(m)和少部分近中部着丝粒染色体(sm)组成。(4)核型类型除了菊叶香藜为1B以外,其余均属于2B类型。(5)在藜麦、灰绿藜及藜中具有分布位置不同、数量不等的双随体。5S rDNA、45S rDNA FISH结果表明:(1)藜麦和灰绿藜的染色体上存在2对5S rDNA位点和1对45S rDNA位点,藜、杂配藜的染色体上存在1对5S rDNA位点和1对45S rDNA位点,菊叶香藜的染色体上只存在1对5S rDNA位点。(2)5S rDNA和45S rDNA位点均位于染色体的短臂上。该研究首次获得了藜属植物基于5S rDNA和45S rDNA荧光原位杂交核型,为藜属植物亲缘关系研究和细胞生物学研究提供了分子细胞遗传学依据。  相似文献   

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七种中国淫羊藿属药用植物细胞分类学研究   总被引:1,自引:0,他引:1  
该研究应用常规压片法对7种中国淫羊藿属药用植物进行了核型分析,为淫羊藿属药用植物的分类及选育等提供理论基础。结果表明:7种淫羊藿属植物体细胞染色体数目均为2n=2x=12,基数x=6;水城淫羊藿、腺毛淫羊藿、保靖淫羊藿、拟巫山淫羊藿、天全淫羊藿5个种均有4对m染色体和2对sm染色体,核型公式均为2n=2x=12=8m(2SAT)+4sm,其中水城淫羊藿、腺毛淫羊藿的核型分析为首次报道;镇坪淫羊藿、偏斜淫羊藿具有3对m染色体和3对sm染色体,核型公式为2n=2x=12=6m(2SAT)+6sm。拟巫山淫羊藿第2对染色体具随体,其余物种第1对染色体均有随体;腺毛淫羊藿、保靖淫羊藿、拟巫山淫羊藿、镇坪淫羊藿、偏斜淫羊藿、天全淫羊藿均属于Stebbins 2A类型,水城淫羊藿为Stebbins 1A类型。结合文献综合分析发现,该属植物不同种间的核型高度一致,核型稳定,种间核型差异小,核型结构与地理分布、形态特征相关性较小。因此,淫羊藿属是一个在核型进化上较为保守的植物类群,用核型分析对该属植物属下进行种类鉴定、遗传演化十分困难,即使是属内远缘物种,其核型系统学的意义有限,但在属上的分类级别有较大的参考价值。  相似文献   

14.
Results of molecular studies regarding the phylogenetic placement of the order Ostropales and related taxa within Lecanoromycetes were thus far inconclusive. Some analyses placed the order as sister to the rest of Lecanoromycetes, while others inferred a position nested within Lecanoromycetes. We assembled a data set of 101 species including sequences from nuLSU rDNA, mtSSU rDNA, and the nuclear protein-coding RPB1 for each species to examine the cause of incongruencies in previously published phylogenies. MP, minimum evolution, and Bayesian analyses were performed using the combined three-region data set and the single-gene data sets. The position of Ostropales nested in Lecanoromycetes is confirmed in all single-gene and concatenated analyses, and a placement as sister to the rest of Lecanoromycetes is significantly rejected using two independent methods of alternative topology testing. Acarosporales and related taxa (Acarosporaceae group) are basal in Lecanoromycetes. However, if the these basal taxa are excluded from the analyses, Ostropales appear to be sister to the rest of Lecanoromycetes, suggesting different ingroup rooting as the cause for deviating topologies in previously published phylogenies.  相似文献   

15.
The karyotypes and chromosomal polymorphism of Chironomus pseudothummi were investigated in different parts of its areal. It was established that chromosomal variability in the natural populations of this species was represented mainly by the inversion polymorphism of arm G. Only rare and unique inversions were found to be heterozygous in arms C, D, and E. In total, 14 banding sequences of polytene chromosomes form the banding sequence pool of C. pseudothummi. Geographic differences in the distribution of chromosomal banding sequences throughout the areal were established. The presence of banding sequences pstG1 and pstG2 is characteristic of European populations. The banding sequence pstG1 disappeared completely with a simultaneous increase in the frequency of pstG2 and with the appearance of a new inversion banding sequence pstG3 in Siberian populations. Differences in the set of rare and unique inversions in arms C, D, and E between the West-European and West-Siberian populations have been revealed.  相似文献   

16.
S. Bjar  J. P. Bouch 《Biochimie》1984,66(11-12):693-700
In an attempt to locate gyrase binding sites in a specific region of the chromosome of E. coli, we have reinvestigated gyrase-promoted cleavage of chromosomal DNA by oxolinic acid and sodium dodecyl sulfate. Contrary to a previous report suggesting the presence of one site every 100 kb of DNA (Snyder and Drlica, J. Mol. Biol. 131, 287-302), we found frequencies of one cleavage every 25 or 12 kb depending on the growth medium. A search for cleavage sites by Southern blot hybridization failed to reveal any binding site cleaved at a high frequency. These results suggest that the actual spacing of sites is much closer than that determined from the frequency of cleavage. Measurement of the average size of fragments containing defined DNA sequences indicated that the frequency of sites varies along the chromosome. The region located opposite to oriC carries relatively few sites.  相似文献   

17.
The fate of most nonhuman primate species is intimately related to man. The increasing encroachment on the natural habitat has resulted in the decimation and even near extinction of some species. Along with this development, the basic concept in many modern zoos has changed from one of merely display to self-perpetuating units. Primate research facilities are orienting their research programs towards reproductive physiology and behavior in an effort to provide basic knowledge of reproduction in these species. This increased emphasis in the area of reproductive biology and the various efforts to improve breeding of these mostly endangered primates in captivity has stimulated the author to write this review. It represents an attempt to provide the reader with basic background information relating to the endocrinology and behavior of reproduction in the clawed New World monkeys as it exists at the time of publication. The intermediate evolutionary position ofCallimico goeldii between the clawed New World monkeys and the ‘true New World monkeys’ and our relatively poor knowledge about reproduction and behavior in this particular species fully justifies the focus on Goeldi’s monkey in this essay. This review is an attempt to provide a brief history of previous studies but also the basis for research in the future. The current status of knowledge of the small-bodied clawed monkeys is also discussed in an evolutionary context, with an emphasis on the different reproductive strategies in this dynamic group of primates. The outcome, not surprisingly, confirms the unique position ofCallimico goeldii in its social, ecological, and evolutionary environment.  相似文献   

18.
该实验以黄果龙葵和龙葵的根尖为实验材料,进行不同的预处理、固定和解离,确定出各种材料适合于核型分析的制片方法。结果表明:龙葵于15℃条件下经0.05%秋水仙素预处理2.5h,固定后用1mol/L HCl酸解后,染色观察,得到的染色体分散,易于染色体计数和形态观察。用此方法对黄果龙葵和龙葵进行核型分析,结果发现:黄果龙葵和龙葵都属于小型染色体,黄果龙葵为四倍体,核型公式为K(4n)=48=4sm+44m,核型不对称系数为56.22%,属于2B核型。龙葵为六倍体,核型公式为K(6n)=72=72m,核型不对称系数为55.89%,属于1B核型。  相似文献   

19.
石蒜科(Amaryllidaceae)葱亚科(Allioideae)葱族(Allieae)葱属(Allium)的Anguinum亚属在中国分布有6种2变种,该亚属植物具有重要的药用价值。该研究在扩大样本量和覆盖范围的基础上,采用常规压片法对葱属Anguinum亚属4种植物19居群的染色体核型进行了研究,首次报道了心叶韭(Allium ovalifolium var.cordifolium)的核型。结果表明:供试类群中茖葱都为四倍体,对叶韭和心叶韭都为二倍体,太白韭具有二倍体和四倍体,染色体基数均为x=8,核型类型都为2A型,每个居群都具有随体染色体,随体染色体多为st染色体,随体均位于短臂末端,并且对叶韭眉县居群和太白韭聂拉木居群存在B染色体。结合前人研究结果讨论了Anguinum亚属植物的染色体特征、随体染色体的多态性和该亚属植物的进化方式,探讨了茖葱(Allium victorialis)和对叶韭(A.listera)的细胞地理学问题。得到如下推论:(1)染色体加倍和结构变异是Anguinum亚属进化的两种重要机制,环境异质性使得Anguinum亚属植物随体染色体具较高的多态性;(2)茖葱通过多倍化和无性繁殖并存来扩大居群;(3)染色体形态变异是对叶韭适应环境变异的重要方式。  相似文献   

20.
The morphology of many hypogeous fungi converges on a homogeneous reduced form, suggesting that disparate lineages are subject to a uniform selection pressure. The primary goal of this study was to evaluate the morphology and infer the phylogeny of the Leucogastrales with Mycolevis siccigleba using a Bayesian methodology. A comprehensive morphological assessment was used for an a priori phylogenetic inference to guide the sequencing effort. All structures except spore ornamentation pointed to the Albatrellaceae as the most likely sister taxon. Polyporoletus sublividus, a close relative of Albatrellus, produces ornamented basidiospores with a similar structure to M. siccigleba basidiospores. The ITS from 30 taxa was used for the molecular phylogenetic analysis. P. sublividus was found sister to Mycolevis. Leucophleps spinispora and L. magnata formed a group sister to the Polyporoletus/Mycolevis group, whereas Leucogaster was polyphyletic with respect to the core of the Leucogastrales and sister to A. caeruleoporus. This relationship was expected as previously undescribed chlamydospores produced by members of Albatrellus had a similar morphology to the basidiospores of L. rubescens.  相似文献   

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