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1.
Blood samples were obtained sequentially from 10 dairy cows around the time of parturition to assess plasma fluctuations in estradiol-17β (E2) levels in association with those of several bone resorption markers. Plasma E2 concentration increased sharply a few days prepartum and decreased quickly after parturition. In terms of bone resorption markers, the plasma level of tartrate-resistant acid phosphatase isoform 5b (TRAP5b) rose significantly, commencing 1 week prepartum, and was maintained at this level to a few days postpartum. The plasma concentration of carboxyterminal collagen cross-links of type-I collagen (CTx) increased significantly after parturition. These observations suggest that osteoclast-mediated bone resorption was activated after parturition when plasma E2 concentrations decreased.  相似文献   
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基于蔗糖代谢基因多态性的甘蔗基因型遗传多样性   总被引:1,自引:0,他引:1  
[目的]探讨利用基于蔗糖代谢酶基因多态性的目标区域扩增多态性(target region amplificationpolymorphism,TRAP)标记进行甘蔗遗传多样性、遗传距离及遗传距离与糖分表型值关联性分析的可行性.[方法]利用4个根据参与蔗糖代谢酶基因SuSy、SPS,SAI和PPDK设计的锚定引物和9个随机引物,筛选具有多态性的17对引物组合,对28个糖分性状表型不同的甘蔗基因型进行TRAP标记,通过分子标记数据,估算不同基因型蔗糖代谢基因的遗传变异和遗传距离,并进行聚类分析.[结果]共扩增出170个条带,其中109个为多态性条带,多态性比率为64.1%,平均每个引物组合产生10个条带,6.4个多态性条带.在所测试的28个甘蔗基因型中,基于蔗糖代谢酶基因多态性所估计的遗传相异系数(genetic dissimilarity,GD)为0.12-O.80.基于GD的UPGMA聚类结果显示,在GD=O.49处,供试基因型可被划分为4类,但就所采集的特定时期的锤度数据而言,类间和类内的锤度表型值没有明显的规律.[结论]甘蔗不同基因型间4个蔗糖代谢酶基因遗传变异较高,多态性丰富,暗示TRAP技术在评价甘蔗蔗糖分性状方面具有应用潜力,但与锤度表型值数据的关联性还有待进一步 研究.  相似文献   
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Framework genetic linkage maps of two progenitor species of cultivated sugarcane, Saccharum officinarum ‘La Striped’ (2n = 80) and S. spontaneum ‘SES 147B’ (2n = 64) were constructed using amplified fragment length polymorphism (AFLP), sequence related amplified polymorphism (SRAP), and target region amplification polymorphism (TRAP) markers. The mapping population was comprised of 100 F1 progeny derived from the interspecific cross. A total of 344 polymorphic markers were generated from the female (S. officinarum) parent, out of which 247 (72%) were single-dose (segregating in a 1:1 ratio) and 33 (9%) were double-dose (segregating in a 3.3:1 ratio) markers. Sixty-four (19%) markers deviated from Mendelian segregation ratios. In the S. spontaneum genome, out of a total of 306 markers, 221 (72%) were single-dose, 43 (14%) were double-dose, and 42 markers (14%) deviated from Mendelian segregation ratios. Linkage maps with Kosambi map distances were constructed using a LOD score ≥5.0 and a recombination threshold of 0.45. In Saccharum officinarum, 146 markers were linked to form 49 linkage groups (LG) spanning 1732 cM whereas, in S. spontaneum, 121 markers were linked to form 45 LG spanning 1491 cM. The estimated genome size of S. officinarum ‘La Striped’ was 2448 cM whereas that of S. spontaneum ‘SES 147B’ was 3232 cM. Based on the two maps, genome coverage was 69% in S. officinarum and 46% in S. spontaneum. The S. officinarum parent ‘La Striped’ behaved like an auto-allopolyploid whereas S. spontaneum ‘SES 147B’ behaved like a true autopolyploid. Although a large disparity exists between the two genomes, the existence of simple duplex markers, which are heterozygous in both parents and segregate 3:1 in the progeny, indicates that pairing and recombination can occur between the two genomes. The study also revealed that, compared with AFLP, the SRAP and TRAP markers appear less effective at generating a large number of genome-wide markers for linkage mapping in sugarcane. However, SRAP and TRAP markers can be useful for QTL mapping because of their ability to target gene-rich regions of the genome, which is a focus of our future research.  相似文献   
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以黑龙江省东北林业大学帽儿山实验林场的3种典型木材腐朽菌为试验材料,采用TRAP分子标记的手段,针对5种木质素与纤维素相关酶基因LiP、MnP、Lac、CBHⅡ、CDH设计引物,初步分析这些编码基因的多态性。试验确定了3种木腐菌TRAP分子标记的反应体系和反应程序。经过对32对引物进行筛选试验,共确定11对引物,包括3对标记MnP编码基因的引物、3对标记Lac编码基因的引物、3对标记CBH编码基因的引物,以及2对标记CDH编码基因的引物。结果表明:3种木腐菌的TRAP-PCR标记共产生了265条条带,其中多态性条带206条,占总条带的77.74%,多态性最高为100%,最低为60%,证明了TRAP分子标记可以应用于木腐菌的遗传分析。  相似文献   
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Cattle from Northern Portugal, many with pulmonary lesions typical of contagious bovine pleuropneumonia, were investigated for the presence of Mycoplasma mycoides subspecies mycoides small colony (MmmSC), which is the causative agent of CBPP, with several detection tests. Sandwich ELISA that included a culture enrichment stage, and 2 different PCR diagnostic systems were used to detect MmmSC in lung and mediastinal lymph node tissues from these animals. The comparison of typical CBPP pathology with the results of detection revealed that no single one of these methods provided a perfect match to the pathological data. Best performing tests were the PCR with laser induced fluorescence and PCR with pleuroTRAP kit (Chemicon, Australia), which are diagnostic systems based on amplification of genomic MmmSC DNA followed by sensitive detection of the amplified products. These were followed by the broth-enriched sandwich ELISA, which uses a monoclonal antibody specific to the M. mycoides cluster, to capture the antigen.  相似文献   
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基于TRAP的长穗偃麦草SCAR标记的开发及应用   总被引:2,自引:0,他引:2  
为了开发长穗偃麦草的特异标记,依据TRAP技术,利用56对固定引物与随机引物的组合对中国春-长穗偃麦草附加系等材料进行PCR扩增,共筛选出160条分布于长穗偃麦草1E-7E染色体的特异扩增片段。通过对104个片段的序列进行同源比对,选择与小麦无同源序列的区段设计138对引物,分别对中国春、长穗偃麦草、中国春-长穗偃麦草附加系进行PCR扩增,最终获得30个长穗偃麦草特异SCAR标记,发展标记的效率为53.6%。利用这些特异SCAR标记对硬粒小麦(AABB)与异源六倍体小麦(AABBEE)杂交产生的F2中38个单株进行扩增鉴定,9个单株仅附加了1条相同的E染色体,其余为多条E染色体或者无E染色体附加。这些SCAR标记在不同材料和世代表现出优越的特异性和稳定性,可用于检测小麦背景中附加的相关长穗偃麦草染色体。  相似文献   
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黄颡鱼遗传图谱构建及生长相关性状的QTL定位   总被引:2,自引:0,他引:2  
以野生(♂)和人工养殖(♀)黄颡鱼杂交的100个F1个体为作图群体,用SSR、SRAP和TRAP3种DNA分子标记技术构建黄颡鱼的遗传连锁图谱。图谱整合了13个SSR标记,89个SRAP标记,26个TRAP标记。其中雌性框架图谱包括16个连锁群,图谱的长度为585.5cM;雄性框架图谱包括15个连锁群,图谱的长度为752.3cM;共享框架图谱包括5个连锁群,图谱的长度为231.3cM。用该连锁图谱对黄颡鱼的5个生长相关性状进行QTL扫描,在雌性图谱上检测到1个头宽的QTL,定位于第七连锁群上,LOD值为3.2,可解释的表型变异为13%。在雄性图谱上分别检测到1个体高和体长的QTL,均定位于第一连锁群上。体高QTL的LOD值为2.4,可解释的表型变异为12%。全长QTL的LOD值为2.1,可解释的表型变异为11%。3个QTL均可用于黄颡鱼的生长性状的标记辅助育种。  相似文献   
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【目的】木质纤维素是重要的可再生资源,白腐菌对降解木质纤维素具有特殊的优势。研究3种白腐菌的生物学特性、酶学活性以及菌种间的遗传多样性,系统分析3种白腐菌木质纤维素酶的表达与相关基因多态性的关系,为高产木质纤维素酶菌种选育提供理论基础,为白腐菌木材降解分子机制的研究提供科学依据。【方法】以云芝栓孔菌、火木层孔菌和松杉灵芝3种白腐菌为研究材料,测定在不同培养温度下固体培养基中菌落的生长速度和液体培养基中的生物量变化,利用比色法测量白腐菌5种木质纤维素酶活性,运用目标区域扩增多态性( TRAP)分子标记分析3种白腐菌的木质纤维素降解相关酶基因的多态性。【结果】在不同温度下(23,28℃),3种白腐菌在PDA固体培养基上的生长速度均为云芝栓孔菌>火木层孔菌>松杉灵芝,云芝栓孔菌和火木层孔菌在28℃的生长速度高于23℃,而松杉灵芝在23℃培养生长更快;液体培养基中云芝栓孔菌的生物量高于火木层孔菌和松杉灵芝。3种白腐菌木质素相关酶活性受木屑诱导显著提高,木质素酶活性最高的是漆酶,其次是木质素过氧化物酶,最低的是锰过氧化物酶;纤维素酶的表达在3种白腐菌中无显著差异,但外切纤维素酶活性明显高于内切纤维素酶活性,玉米秸秆为碳源诱导产生的纤维素酶活性明显高于木屑碳源样品。云芝栓孔菌更偏好于木质素酶的表达,而火木层孔菌和松杉灵芝则更偏好于纤维素酶的表达。TRAP分子标记扩增结果显示,木质素酶相关基因的6对引物共产生109条条带,多态性条带为79条,多态性百分比为72.47%;纤维素酶相关基因的11对引物共产生198条条带,多态性条带为140条,多态性百分率为70.70%。【结论】通过生长速度、生物量、木质纤维素酶活性的检测以及 TRAP 分子标记结果表明3种白腐菌在种间具有较高的遗传差异。3种白腐菌木质素酶活性的大小与其酶基因多态性之间没有明显的对应关系;3种白腐菌纤维素酶活性大致相同,其基因多态性也比较一致。  相似文献   
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为了建立柿属植物目标区域扩增多态性(TRAP)标记技术体系,对影响TRAP-PCR的Mg2+、dNTPs、Taq DNA聚合酶、固定引物和随机引物浓度比5个因素进行了优化。确定优化的反应体系为:模板DNA 40 ng,buffer 1×,Mg2+1.4 mmol/L,dNTPs 0.2 mmol/L,固定引物和随机引物浓度比为11∶1,Taq酶0.5 U,反应总体积为15μL。利用柿属植物EST数据库信息设计锚定引物10条,与11条随机引物组合共110对引物。利用这些引物对柿属植物6个基因型进行TRAP-PCR扩增,其中84个引物组合能扩增出清晰条带,占引物总量的76.36%;36个引物组合表现出良好的多态性扩增,并在20份柿属植物中进行了引物验证。  相似文献   
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