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1.
降钙素基因相关肽肽段的抗原性和免疫原性 总被引:2,自引:0,他引:2
用固相合成法合成了有关降钙素基因相关肽CGRP五个肽段。它们的氨基酸顺序分别为:CGRP-1(24-37);CGRP-2(14-37);CGRP-3(9-23);CGRP-4(1-23)和CGRP-5(1-13)。用酶标方法测定了它们的抗原性,发现CGRP-2和CGRP-1能够很好地与抗CGRP抗血清结合。将CGRP-1;CGRP-3和CGRP-5分别免疫兔子,获得的抗血清分别与CGRP进行反应, 相似文献
2.
安徽黄山西部青冈种群小地理范围的遗传分化 总被引:18,自引:0,他引:18
采用垂直板型聚丙烯酰胺凝胶电泳研究了黄山西部青冈〔Cyclobalanopsisglauca(Thunb.)Oerst.〕种群小地理范围的遗传分化。黄山2个亚种群之间基因频率基本没有差异,基因多样性平均为0.1826,小岭和钓桥亚种群分别有2个和1个位点存在显著的杂合子不足的现象。亚种群之间的遗传分化程度很低(GST=0.976%),主要是由于小地理范围的生境异质性程度低和较大的基因流(平均为173)造成的。 相似文献
3.
用固相合成法合成了有关降钙素基因相关肽CGRP五个肽段。它们的氨基酸顺序分别为:CGRP-1(24-37);CGRP-2(14-37);CGRP-3(9-23);CGRP-4(1-23)和CGRP-5(1-13)。用酶标方法测定了它们的抗原性,发现CGRP-2和CGRP-1能够很好地与抗CGRP抗血清结合。将CGRP-1;CGRP-3和CGRP-5分别免疫兔子,获得的抗血清分别与CGRP进行反应,发现只有抗CGRP-1的抗血清能够与CGRP很好地结合。因此,可以推测CGRP的羧端部分是其免疫活性部位。 相似文献
4.
山茶属17个种的核形态学研究 总被引:12,自引:4,他引:8
研究了山茶属的9个组17个种的细胞核形态结构,它们的间期核和分裂前期染色体的构形均为球形前染色体形和中间形。体细胞分裂中期的染色体构形,即核型分别为:红山茶组:1.贵州红山茶2n=90=62m(2sat)+22sm+6st。2.南山茶2n=30=23m(4sat)+5sm+2st,3.木果红山茶2n=60=32m(1sat)+24sm(2sat)+4st;茶组;4.大理茶2n=30=23m+7sm 相似文献
5.
东亚钳蝎神经毒素在大肠杆菌中的表达 总被引:2,自引:0,他引:2
以山西风陵渡东亚钳蝎(ButhusmartensiKarsch)的尾腺总RNA为模板,根据已知的蝎神经毒素保守氨基酸序列设计引物,利用PCR技术,扩增并克隆了两个蝎神经毒素基因.序列分析表明,由两个基因导出的氨基酸序列(BmKMm1和BmKMm2)与已知的蝎神经毒素BmKⅠ、BmKⅡ、BmKⅢ、BmKM1、BmKM9有很高的同源性.将BmKMm2基因重组到大肠杆菌分泌型表达载体pExSec1中进行表达.SDS-PAGE证明表达产物被分泌到细胞周间质及培养液中.经IgG-Sepharose纯化后的蛋白质注射小白鼠表明表达产物有生物学活性 相似文献
6.
本文利用凝胶电泳法研究亮叶水青冈(Faguslucida)种内遗传多样性。所测定的酶系统包括:过氧化物酶(PX1和PX2)、磷酸葡萄糖脱氢酶(PGD)、谷氨酸草酰乙酸转氨酶(GOT1和GOT2)、异柠檬酸脱氢酶(IDH)、甲基荼醌还原酶(MNR)、葡萄糖磷酸变位酶(PGM1和PGM2),苹果酸脱氨酶(MDH2)、酸性磷酸酶(ACP)和磷酸果糖升构酶(PGI)9种酶系统11个基因位点。测定和分析了亮叶水青冈2地理种群的等位基因频率,固定指致,基因多祥性和遗传距离,为进一步研究水青冈的遗传变异和种内种间关系提供了科学依据。 相似文献
7.
高粱是世界上第五大主要粮食作物,也是非洲国家的主要粮食来源之一,Striga asiatica是一种寄生于高粱等主要农作物的野生草之一。选用两个对寄生草抗性表现差异的 高粱品系“山桂红”和“SRN39”作亲本,构建了一个重组近交系群体(Recombinant inbred, RI),并随机筛选出94个系用于构建分子连锁图谱和基因定位。在应用的286个多态性标记 中,有251个标记分别标定在10条不同的连锁群上,标记间的平均图距为7.1cm,总图谱覆盖 了高粱基因组的1779cm,是目前国际上几个比较完整的高粱分子连锁图谱之一。群体的共 分离分析表明,与寄生草抗性有关的萌发诱导物基因(Germinination stimulant gene-GermStim) 位于高粱的遗传连锁群J上,相距较近的分子标记为13cm。进一步的精细定位分析,发现有 两个分子标记分别位于基因的两侧,距离为1.6和2.1个cm。 相似文献
8.
9.
以聚丙烯酰胺凝胶电泳方法测定了331例辽宁满族新生儿脐带血血红蛋白F中Gγ/Aγ比值。结果显示:高Gγ(>80%)者4例,占1.21%,其基因频率(f)为0.00604,低Gγ(30-48%)者6例,占1.81%,其基因频率为0.00906,其余正常,Gγ平均值为65.23±6.38%。未发现AγT链。对其中八例异常者(4例高Gγ值,4例低Gγ值)的染色体DNA进行了基因图谱分析,确定4例高Gγ值 相似文献
10.
为研究代谢型谷氨酸受体各亚型在猫脊髓内的定位分布特征,本实验采用免疫组织化学方法调查了代谢型谷氨酸受体五种亚型(mGluR1,mGluR2,mGluR3,mGlur5及mGluR7)在猫脊髓(颈2、颈6、胸5、腰6、骶1-2)内的分布状况。结果如下:(1)在背角深层(Ⅲ-Ⅳ层)和腹角内分布有大量中小型(<30μm)mGluR1样免疫反应阳性神经元,背角浅层(Ⅰ、Ⅱ层)为阴性;(2)mGluR2/3样免疫反应阳性产物仅见于背角Ⅱ层内侧部,其它部位为阴性;(3)致密的mGluR5样免疫反应阳性产物主要分布于猫脊髓背角Ⅱ层的神经毯内,背角Ⅰ层及深层呈中等密度染色;(4)致密的mGluR7样免疫反应阳性产物分布于背角Ⅱ层的神经毯内,背角Ⅰ层及深层(Ⅲ-Ⅳ层)呈中等密度染色。此外,腹角运动神经元和骶髓副交感核内的神经元亦呈现mGluR7样免疫反应阳性。单侧切断背根,发现术侧背角浅层内mGluR7样免疫反应阳性产物密度略有降低,而mGluR5样免疫反应阳性产物密度与对侧基本相同。本研究结果显示代谢型谷氨酸受体五种亚型在所调查的猫脊髓各节段内(颈2、颈6、胸5、腰6、骶1-2)的分布存在差异,提示它们在介导谷氨酸传递的信 相似文献
11.
Freddy Bugge Christiansen 《Journal of genetics》1987,66(1):45-67
The balance between the creation of associations between alleles at different loci by immigration and the convergence to linkage equilibrium due to the recombination process is studied in a theoretical model. The geographical structure of the model is a stepping-stone chain of populations linking two genetically constant source populations. The model assumes an arbitrary number of autosomal loci and considers genetic variation (two alleles at each locus) that is not subject to natural selection. The gene frequencies at each locus will then show a linear cline through the stepping-stone chain of populations. The deviation from linkage equilibrium through the stepping-stone cline is characterized by an equation for linear measures that provide the linkage disequilibrium measures for a given set of loci in terms of the gene frequencies and the linkage disequilibria in the source populations and in terms of the linkage disequilibrium measures through the cline for lower numbers of loci. Numerical examples of this iterative solution are given, and it is shown that the build-up of the higher order Bennett-disequilibria through the cline is considerably more pronounced than the build-up of two-locus disequilibria. 相似文献
12.
DNA sequence variation and latitudinal associations in hsp23, hsp26 and hsp27 from natural populations of Drosophila melanogaster 总被引:2,自引:0,他引:2
Heat shock genes are considered to be likely candidate genes for environmental stress resistance. Nucleotide variation in the coding sequence of the small heat shock genes (hsps) hsp26 and hsp27 from Drosophila melanogaster was studied in flies originating from the Netherlands and eastern Australia. The hsp26 gene was polymorphic for an insertion/deletion of three extra amino acids and two nonsynonymous changes in all populations. The hsp27 gene exhibited two nonsynonymous changes and three synonymous mutations. The hsp26 polymorphism showed a latitudinal cline along the east coast of Australia. This pattern was not confounded by the fact that the shsps are located in the inversion In(3 L)P which also shows a latitudinal cline in eastern Australia. A similar latitudinal cline was found for the previously described variation in hsp23, while frequencies of hsp27 alleles did not change with latitude. These findings suggest that variation at two of the shsps or closely linked loci are under selection in natural populations of D. melanogaster. 相似文献
13.
H Matsumoto T Miyazaki X Xu H Watanabe N Kawai K Suzuki 《American journal of physical anthropology》1986,70(2):161-165
Serum samples from five populations in China [173 from Huhehote (Naimengu Zhizhiqu), 195 from the Beijing area, 131 from Hefei (Anhui Province), 155 from Hangzhou (Zhejiang Province), and 152 from Guangzhou (Guangdong Province)] were tested for G1m(1, 2, 3, and 17), G2m(23), G3m(5, 10, 11, 13, 14, 15, 16, 21, and 26), and Km(1). The Gm pattern of the Chinese populations are characterized by the presence of four haplotypes, Gm1, 17;..;21, 26, Gm1, 2, 17;..;21, 26, Gm1, 17;..;10, 11, 13, 15, 16, and Gm1, 3;23;5, 10, 11, 13, 14, 26, which are characteristic of Mongoloid populations. Agreement was obtained in all Chinese samples between the observed and expected frequencies on the basis of the Hardy-Weinberg equilibrium of phenotypes. Heterogeneity tests of the haplotypic distributions among the five populations showed no significant differences in the distributions of Gm phenotypes between Huhehote and Beijing nor between Hefei and Hangzhou, whereas highly significant differences were observed among the three districts: northern part (Huhehote and Beijing), central part (Hefei and Hangzhou), and southern part (Guangzhou). The data indicate a south to north genocline, ranging from Huhehote to Guangzhou in which Gm1, 17;..;21, 26 changes from 0.471 to 0.183, Gm1, 17;..;10, 11, 13, 15, 16 from 0.097 to 0.033, and Gm1, 3;23;5, 10, 11, 13, 14, 26 from 0.229 to 0.730. In contrast to the Gm system, no significant regional differences in the frequencies of the Km1 allele were observed among the five populations. 相似文献
14.
Genetic Drift in Clines Which Are Maintained by Migration and Natural Selection 总被引:3,自引:0,他引:3
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Joseph Felsenstein 《Genetics》1975,81(1):191-207
Genetic drift will cause a migration-selection cline to wobble about its expected position. A rough linear approximation is developed, valid when local populations are large. This is used to calculate effects of genetic drift on clines in a stepping-stone model with abrupt and with gradual changes of selection coefficients at a single haploid locus. Among the quantities calculated are measures of slope, standardized variation of gene frequencies around their expected values, and correlation among neighboring populations with respect to deviations from the expected gene frequencies. These quantities appear to be primarily functions of Ns and Nm for a given pattern of selection. Computer simulation gives rough confirmation of these results. Standardized variances of gene frequencies and correlation of neighbors differ along the cline in the case of smooth changes in selection. In no case is pathological behavior of gene frequency deviations found near the boundaries of selective regions. Local behavior of gene frequences of nearby colonies is approximately predicted by a simple adaptation of the stepping-stone theory of Kimura and Weiss. Approximate measures of the lateral variation of the midpoint of a cline and the probability of non-monotonicity are also calculated and discussed. 相似文献
15.
MASAHITO T. KIMURA AKIRA BESSHO ZHUO-HUA DAI 《Biological journal of the Linnean Society. Linnean Society of London》1993,48(4):335-341
Temperate species belonging to the Drosophila auraria species complex, D. auraria Peng, D. biauraria Bock & Wheeler, D. triauraria Bock & Wheeler and D. subauraria Kimura, enter reproductive diapause to pass the winter in response to short daylengths. These species from Japan showed latitudinal clines in critical daylength which is longer in populations from higher latitudes. The slopes of these clines coincided well with that of the cline which is approximately predicted from climatic data, suggesting that these clines result from adaptation of the species to the latitudinal gradient of climatic conditions. Between the mainlands and the surrounding islands of Japan, the slopes of clines did not differ significantly, but the deviation from the regression line was usually smaller in mainland populations. It is assumed that gene flow reduces the genetic variation among mainland populations and results in the development of smooth clines. In the plain of east China, D. triauraria did not show clinal variation in critical daylength, although the development of the cline is expected from climatic data. Extensive gene flow among Chinese populations is considered to prevent the development of a cline. 相似文献
16.
Serum samples from two populations of Catalonia, Spain, 208 from Olot (Gerona) and 209 from Tortosa (Tarragona), were typed for G1m (1, 2, 3, 17), G3m (5, 10, 11, 13, 14, 15, 16, 26), and Km (1). The Gm patterns of the Catalonian populations are characterized by the presence of four haplotypes, Gm 1,17;21,26 Gm 1,2,17;21,26 Gm 1,3;5,10,11,13,14,26 and Gm 3;5,10,11,13,14,26. The homogeneity for haplotype Gm 1,17;21,26 among our data and other European populations suggests the existence of an isofrequency line which starts from the Mediterranean zone of Iberian Peninsula and continues through the northwestern part of Europe. From this line a decreasing cline towards the south can be observed. For the haplotype Gm 1,2;17,21,26, affinities are observed between Catalonian populations and other populations from central Europe. This confirms the existence of a gradient towards low values from NW to SE. The presence of the typical Mongoloid haplotype Gm 1,3;5,10,11,13,14,26 is discussed in this paper. No significant differences in the frequencies of the Km1 allele were observed among the European populations. 相似文献
17.
Mutations in the gene encoding connexin-26 (specified GJB2) have been shown to be a major cause of nonsyndromic recessive deafness (NSRD), and a single mutation 35delG in the GJB2 gene accounts for the majority of cases of NSRD. This mutation was screened in France and in other European populations by a reliable PCR method. We present here a meta-analysis of the 35delG frequencies in 4123 random controls from 20 European countries, and show that the mutation is more frequent in the south of Europe than in the north; a north-south increasing cline of 35delG frequencies is established (r = -0.527). 相似文献
18.
Latitudinal variation of the polymorphic sn-glycerol-3-phosphate (alpha-Gpdh) locus in Drosophila melanogaster has been characterized on several continents; however, apparent clinal patterns are potentially confounded by linkage with an inversion, close associations with other genetic markers that vary clinally, and a tandem alpha-Gpdh pseudogene. Here we compare clinal patterns in alpha-Gpdh with those of other linked markers by testing field flies from eastern Australian locations collected in two separate years. The alpha-Gpdh variation exhibited a consistent non-linear cline reflecting an increase in the alpha-GpdhF allele at extreme latitudes. This pattern was not influenced by the In(2L)t inversion wherein this locus is located, nor was it influenced by the presence of the alpha-Gpdh pseudogene, whose presence was ubiquitous and highly variable among populations. The alpha-Gpdh pattern was also independent of a cline in allozyme frequencies at the alcohol dehydrogenase (Adh) locus, and two length polymorphisms in the Adh gene. These results suggest clinal selection at the alpha-Gpdh locus that is partially or wholly unrelated to linear climatic gradients along the eastern coast of Australia. 相似文献
19.
Alida Cornelia Ebeli-Struijk Elisabetta M. Wurzer-Figurelli Franco Ajmar P. Meera Khan 《Human genetics》1976,34(3):299-306
Summary Blood samples collected from a number of human populations belonging to various ethnic groups were screened on cellogel for red-cell esterase D (ESD) variants. These data gathered during the present study together with those that have already appeared in the literature indicate that the common variant allele ESD
2 occurs most frequently in the Mongoloid populations, least frequently in the Negroid, and with intermediate frequencies in the Caucasoids. An east to west cline was noticed in the northern populations of the Indian subcontinent; ESD
2 gene frequencies in these populations were found to range between those among the Mongoloids and the Caucasoids. 相似文献