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1.
利用SSR标记分析栽培种花生多态性及亲缘关系   总被引:20,自引:0,他引:20  
利用11对SSR引物对24个花生栽培品种(包括四大类型)进行PCR扩增分析,其中4对检测到明显的多态性,共检测到33个等位基因变异,每一个位点上检测到的等位变异数为5~13个,平均为8.25个。根据扩增结果可以将24个品种中的21个相互区分。供试品种间的遗传相似系数值在0.2~1.0之间,平均为0.4788。根据UPGMA聚类分析结果,供试  相似文献   
2.
八眉猪DQA基因编码区多态性及生物信息学分析   总被引:1,自引:0,他引:1  
采用克隆测序的方法对八眉猪DQA基因编码区进行多态性分析,并利用生物信息学方法预测八眉猪DQA基因的理化特性及其编码产物的结构功能。结果显示:八眉猪DQA基因编码255个氨基酸,编码区序列有14个碱基变异,11个氨基酸变异,外显子2区域表现出丰富的多态性。DQA基因编码产物是一种不稳定的水溶性蛋白,二级结构为混合型,三级结构由α-螺旋、β-折叠、β-转角和无规则卷曲组成。蛋白质功能预测结果显示,信号转导、受体、胁迫应答、免疫应答和生长因子的几率较高。研究结果为八眉猪的抗病分子育种和经济性状相关基因筛选提供理论依据。  相似文献   
3.
Seedlings of Pistacia vera L. developed from seeds of two separate populations in Turkmenistan, Kepele and Agachli, were evaluated for their growth potential and genetic polymorphism. Plant growth rate as well as random amplified polymorphic DNA (RAPD) analysis showed distinct differences between the two populations. In plant height growth rate, 17 Agachli accessions were 1.3 times higher on average than that of 10 accessions of Kepele (significant at p = 0.046) and 1.2 times higher for trunk diameter growth rate (p = 0.062). Cluster analysis divided most accessions into two main genetic groups according to their geographic origin. The Agachli group was further divided into two subgroups. One Kepele accession (K4), was genetically different from the rest and clustered on a separate outgroup. Two Agachli accessions (A12 and A17) were outside the two main populations clusters. Accessions K9 and K10 from Kepele were exceptional and were clustered in each of the two Agachli's subgroups, indicating a close genetic relationship between the two populations. In addition, high similarity values (0.58–1.00) and small genetic distances reflect plausible gene flow between Kepele and Agachli, which are 100 Km apart. Mantel test revealed significant relationship between the RAPD and the morphological traits matrices, pointing to the genetic basis for the measured differences in the growth rate. Growing the accessions on the same plot, under similar conditions enabled the evaluation of genotypic differences. The combination of morphological traits and molecular markers will further assist in preservation of genetic variability and cultivation of useful genotypes of P. vera L.  相似文献   
4.
The development of EST-SSR in foxtail millet (Setaria italica) for polymorphism and transferability study was reported here. From 1213 EST sequences, 30 SSRs were obtained and primers were designed for 26 SSRs. Among them, four pairs of SSR primers amplified polymorphic products in 12 foxtail millet cultivars and one accession of Setaria viridis, a wild relative of foxtail millet, with 10 alleles detected for the four loci and 2.5 alleles per locus. In addition, ten SSR markers could be transferred to other nine Gramineae species. The putative functions of 11 ESTs containing polymorphic and transferable SSRs were also identified.  相似文献   
5.
The previously found wide range in the ratios of avenin or methanol-precipitated fractions to residual proteins was revisited by studying 75 oat varieties, mainly representing landraces from Finland, and included old varieties or selections, cv. Kytö, synthetic hexaploid oats and an Avena strigosa line (HA 71–87). The means of the fraction ratios ranged from 4.17 to 6.46 with significant differences. Samples of 10 narrow-ratio and 10 wide-ratio oats were compared more closely. The wide-ratio sample had significantly higher total protein content and significantly lower content of the methanol-precipitated protein fraction. Therefore, both fractions in general appear to contribute to the ratio of the protein fractions. The wide-ratio sample had significantly lower grain mass and husk-free karyopsis mass. Samples of the extreme ends in the ratios of the protein fractions showed different electrophoretic protein patterns, which was also seen in samples representing the same population of origin. It is evident that polymorphisms in the protein fractions would allow breeding of oat cultivars showing further lowering of proteins putatively toxic to coeliacs assuming oats contain these toxic proteins.  相似文献   
6.
DGAT1基因作为影响奶牛产奶和肉牛肉质性状的主效基因之一,引起了人们越来越多的关注。本文应用生物信息学方法比较了人、牛、猪、绵羊等24个物种的DGAT1基因编码区(CDS)核苷酸和蛋白质序列,并对该基因的遗传多样性进行了分析。结果表明,DGAT1基因的CDS核苷酸和蛋白质序列长度多样性丰富;具有终止密码子偏爱性,包括牛在内的所有脊椎动物终止密码子都为TGA;在长度为1 187bp的33条基因序列中检测到992个多态位点,共生成26种单倍型。从聚类分析图可以看出,脊椎动物、无脊椎动物、植物和微生物的DGAT1基因之间存在着进化分歧,但界内差异较小。  相似文献   
7.
AIM: To investigate the correlation between extracellular signal-regulated kinase 5 ( ERK5 ) -322G/T polymorphism (rs3866958) and the susceptibility to sporadic colorectal cancer (CRC) in southern Chinese population. METHODS: ERK5 -322G/T genotypes were determined by Taqman-MGB probes in 835 CRC cases and 908 healthy controls. RESULTS: No significance of ERK5 -322G/T genotype distribution between CRC patients and controls was observed, but -322G/T decreased the susceptibility to CRC in fat people whose BMI was ≥ 24 kg/m2. Compared to GG genotypes, the carriers with GT and TT genotypes had a significant decrease in the risk of CRC(OR=0.576,95%CI 0.413-0.804, P<0.01). CONCLUSION: ERK5 -322G/T polymorphism (rs3866958) has no significant relevance with sporadic CRC susceptibility, but decrease, the risk of CRC in people with fatness. The T variant genotype is an independent protective factor against sporadic CRC of overweight patients in southern Chinese population.  相似文献   
8.
羊肚菌菌丝和菌核的形成及形态变化多样,了解掌握在不同营养栽培条件下的多态性规律是羊肚菌研究中的难题,对菌丝、菌核微观和宏观形态变化进行综述,并对菌丝、菌核优劣培养条件进行比较分析,为攻克菌核、菌丝多态性在羊肚菌研究中产生的难题及实现羊肚菌人工商业化生产,提供数据及借鉴。  相似文献   
9.
10.
猪乳中一组高分子量多态性蛋白质的同源性鉴定   总被引:1,自引:1,他引:0  
 利用硫酸铵沉淀、凝胶过滤层析和阴离子交换层析等方法从猪乳中分离纯化高分子量蛋白质B (HMWP-B)。 制备兔抗HMWP-B的多克隆抗体,免疫印迹结果表明,不同带型的HMWP之间存在免疫交叉反应,说明该组蛋白具有同源性,为其多态性假说提供了证据。  相似文献   
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