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植物细胞壁富含羟脯氨酸糖蛋白生化特性及基因克隆的研究分成三部分: 第一部分,首先从胡萝卜愈伤组织的细胞壁中获得0.2M氯气钙可溶性蛋白质组分, 经10% TCA沉淀及羧甲基纤维素层析,分离得到一个伸展蛋白,并以SDS-聚丙烯酰胺凝胶电泳,氨基酸组成分析,分子电镜观察对所得的伸展蛋白进行了鉴定,结果表明,在胡萝卜愈伤组织中只存在一种伸展蛋白;SDS-聚丙烯酰胺凝胶电泳的考马斯蓝染色和PAS反应均为阳性,表明伸展蛋白除蛋白质组分还含有糖基;氨基酸组成分析表明,羟脯氨酸的克分子含量约占全部氨基酸的40%,丝氨酸的克分子含量约为羟脯氨酸的四分之一,含有大量的碱性和中性氨基酸,而只含有非常少量的酸性氨基酸,并且这些氨基酸克分子百分数也接近于胡萝卜富含羟脯氨酸糖蚤白基因推测出的克分子百分数。这些结果表明已经得到了一个电泳纯的伸展蛋白。伸展蛋白分子电镜观察证明它是一个棒状分子,长度为87纳米。 第二部分,用得到的伸展蛋白免疫家兔和大鼠,得到的抗体的免疫双扩散效价分别为1:2和1:1,用酶联免疫吸附分析测定的兔抗体效价为1:12,800,同时还建立了竞争性酶联免疫吸附分析测定伸展蛋白含量的标准曲线,线性范围为10-0.00001微克。利用得到的抗体对大豆下胚轴伸展蛋白的合成进行了研究。免疫荧光定位表明,大豆下胚轴表皮细胞及表皮下几层薄壁细胞有大量的荧光标记,并且这些荧光标记大部分分布在细胞质内。大豆下胚轴O.lM Tris-HCl pH7.4和0.2M氯化钙的提取物Western Blotting分析证明0.2M氯化钙提取物有与胡萝卜伸展蛋白电流性质相似的组分,并且这个组分在真菌诱导物处理的大豆下胚轴中的积累明显高于受伤处理的下胚轴。受伤和真菌诱导物处理大豆下胚轴中伸展蛋白积累的变化已经用Western Blotting分析和斑点酶联免疫吸附分析来观察,发现真菌诱导物处理的对灰斑病抗性的大豆下胚轴能够较快地积累伸展蛋白(24 - 48小时),而敏感品系的大豆下胚轴则合成伸展蛋白较晚(43-72小时)。在观察大豆下胚轴免疫荧光定位也发现类似的结果。对伸展蛋白基因的转录活性的初步研究认为抗性品系的大豆下胚轴同源mRNA转录可能早于24小时,而敏感品系大豆下胚轴同源mRNA转录可能在24小时后。以上结果认为大豆下胚轴含同源的mRNA和蛋白质组分,因此推测大豆基因组DNA有伸展蛋白基因。 第三部分,根据第二部分得到的结果,用已经得到的编码胡萝卜伸展蛋白的基因(克隆于pUC8质粒载体中)作探针,与大豆基因组DNA的EcoRI部分酶解片段杂交寻找大豆伸展蛋白基因,已经发现四个片段与探针DNA有同源性。它们的分子量分别约为23kb,8kb,5kb和2.8kb,并且23kb片段可能有更高的同源性。将23kb片段插入pUC9质粒载体上进行可隆,并用菌落原位杂交筛选获得5个克隆,对其中两个克隆用ECoRI酶解并进行分子杂交分析,重组质粒被EcoRI切成四个片段。2.8kb片段为pUC9栽体,2kb片段为与pDC5AI质粒伸展蛋白同源性较好的片段。对于23kb片段的重组质粒有待于进一步的分析。

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Chromosome homologies between the Japanese raccoon dog (Nectereutes procyonoides viverrinus, 2n = 39 + 2-4 B chromosomes) and domestic dog (Canis familiaris, 2n = 78) have been established by hybridizing a complete set of canine paint probes onto high-res

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DNA不仅是主要的遗传物质, 同时也是生物进化史的重要记录者。通过DNA序列分析研究生物的进化历程、确定物种间的进化关系至少有三大优越性。因此, DNA序列分析已成为生物系统与演化研究中最重要与最热门的工具之一, 并取得令人瞩目的结果。

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根据外部形态、头骨特征及地理分布, 对猕猴在中国的亚种分类进行了重新 整理。结果表明M.m.mulatta、M.m.breuicaudus、M.m.lasiotis、M.m.littoralis 和M.m.uestita均为有效亚种, M.m.tcheliensis可能也是一有效亚种。图1表3参 15

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1. The stripe-backed weasel Mustela strigidorsa is one of the rarest and least-known mustelids in the world. Its phylogenetic relationships with other Mustela species remain controversial, though several unique morphological features distinguish it from congeners. 2. It probably lives mainly in evergreen forests in hills and mountains, but has also been recorded from plains forest, dense scrub, secondary forest, grassland and farmland. Known sites range in altitude from 90 m to 2500 m. Data are insufficient to distinguish between habitat and altitudes which support populations, and those where only dispersing animals may occur. 3. It has been confirmed from many localities in north-east India, north and central Myanmar, south China, north Thailand, north and central Laos, and north and central Vietnam. Given the limited survey effort, the number of recent records shows that the species is not as rare as hitherto believed. Neither specific nor urgent conservation needs are apparent.

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We are grateful to all the voluntary donors of DNA samples in this study. We thank Hui Zhang and Yan-jiao Li for their technical help. We also thank Dr. Darren Curnoe for his critical reading of the manuscript. This study was supported by grants from the National 973 project of China (2007CB947701,2007CB815705), the Chinese Academy of Sciences (KSCX1YW-R-34, Westlight Doctoral Program), the National Natural Science Foundation of China (30525028, 30700445, 30630013 and 30771181), and the Natural Science Foundation of Yunnan Province of China (2007C100M, 2009CD107).

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该文首次报道了在典型涡鞭毛虫类中也有含有多种染色质碱性蛋白并且很相似于组蛋 白(至少在分子量上)的情形, 为揭示和澄清组蛋白的起源进化问题提供了新的实验依据 。

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鲤亚科系由ba亚科派生出的单源群, 故以两亚科的性状比较, 以确定为祖征或离征。有25项性状镶嵌分布于鲤亚科5个属中, 根据此性状和简约性原则, 推出鲤亚科系统发育分支图, 证实了原鲤属与鲤属关系较近, 而ba鲤属较早地从鲤亚科中分出, 而与亚科内其他4个属关系较远。又以化石资料分析了鲤亚科的分化时间。图7表4参14

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黑叶猴(Presbytis francoisi)所测的外形结构23项变量,由5个小聚类组成。黑叶猴的外形整体结构与其他一些灵长类比较,更接近于食蟹猴和长鼻猴,其次接近于蜘蛛猴。 图6表2参21