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Yuanxia Liu Jinhao Lan Caihong Wang Baohua Li Jun Zhu Chunxiao Liu Hongyi Dai 《Plant Breeding》2017,136(1):119-125
Apple Glomerella leaf spot (GLS) is a severe fungal disease that damages apple leaves during the summer in China. Breeding new apple varieties that are resistant to the disease is considered the best way of controlling GLS. Fine mapping and tightly linked marker are critically essential for the preselection of resistant seedlings. In this study, a population of 207 F1 individuals derived from a cross between ‘Golden Delicious’ and ‘Fuji’ was used to construct a fine simple sequence repeat (SSR)‐based genetic linkage map. The position of Rgls, a locus responsible for resistance to GLS, was identified on apple linkage group (LG) 15 using SSR markers CH05g05 and CH01d08, which was adapted from a published set of 300 SSR markers that were developed using the bulked segregant analysis (BSA) method. These two SSR markers flanked the gene, and its recombination rate was 8.7% and 23.2%, respectively. A total of 276 newly developed SSR markers around the target region and designed from the genome apple assembly contig of LG15 were screened. Only nine of these were determined to be linked to the Rgls locus. Thus, a total of 11 SSR markers were in linkage with Rgls, and mapped at distances ranging from 0.5 to 33.8 cM. The closest marker to the Rgls locus was S0405127, which showed a genetic distance of approximately 0.5 cM. The first mapping of the gene Rgls was constructed, and the locations of the 11 effective primers in the ‘Golden Delicious’ apple genome sequence were anchored. This result facilitates better understanding of the molecular mechanisms underlying the trait of resistance to GLS and could be used in improving the breeding efficiency of GLS‐resistant apple varieties. 相似文献
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以35份富士苹果(Malus×domestica Borkh.‘Fuji’)芽变材料为试材,利用甲基化敏感扩增多态性(Methylation Sensitive Amplified Polymorphism,MSAP)分析和UPGMA聚类方法,对其基因组甲基化修饰水平、变异模式以及表观遗传变异关系进行研究。结果表明:(1)不同富士系得到不同的MSAP扩增,总DNA甲基化水平27.90%~36.16%,平均32.87%,双链全甲基化为主要甲基化方式;(2)富士芽变材料绝大多数位点保持了原有甲基化模式;(3)绝大多数芽变(68.57%)检测到全部的甲基化变异模式(12种),去甲基化频率极显著高于甲基化频率(P <0.01),且CG去甲基化极显著高于CHG;(4)36份种质遗传相似系数平均值0.89(0.79~0.92),在聚类图上,富士原种分布在芽变系集中区外,新近发生的芽变系更倾向于聚在一起,着色系片红型和条红型芽变呈分散排布状态。总的来看,富士芽变的甲基化变异模式丰富,超甲基化和去甲基化相伴发生,但以去甲基化为主;‘富士’着色芽变与其最原始品种富士,以及芽变之间发生了较大表观遗传变异;片红和条红型芽变聚类未表现明显偏好性。本研究将为进一步开展富士着色系芽变机理研究提供指导,可以CG去甲基化为切入点展开深入研究。 相似文献
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Peritrophic matrix/membrane (PM) critically prevents the midgut of insects from external invasion by microbes. The proteins in the peritrophic membrane are its major structural components. Additionally, they determine the formation and function of this membrane. However, the role of PM proteins in immune regulation is unclear. Herein, we isolated a novel PM protein (MdPM-17) from Musca domestica larvae. Further, the function of MdPM-17 in regulating host innate immunity was identified. Results showed that the cDNA of MdPM-17 full is 635 bp in length. Moreover, it consists of a 477-bp open reading frame encoding 158 amino acid residues. These amino acid residues are composed of two Chitin-binding type-2 domain (ChtBD2) and 19 amino acids as a signal peptide. Moreover, tissue distribution analysis indicates that MdPM-17 was enriched expressed in midgut, and moderate levels in the fat body, foregut, and malpighian tubule. Notably, MdPM-17 recombinant protein showed high chitin-binding capacity, thus belongs to the Class III PM protein group. MdPM-17 protein silencing via RNA interference resulted in the expression of antimicrobial peptide (defensin, cecropins, and diptericin) genes, and this occurred after oral inoculation with exogenous microbes Escherichia coli (Enterobacteriales:Enterobacteriaceae), Staphylococcus aureus (Bacillales:Staphylococcaceae), and Candida albicans (Endomycetales:Saccharomycetaceae)). Therefore, all the antimicrobial peptide (AMP) gene expression levels are high in MdPM-17-depleted larvae during microbial infection compared to controls. Consequently, these findings indicate that MdPM-17 protein is associated with the antibacterial response from the housefly. 相似文献
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The inhibition effect of chitooligosaccharides from housefly larvae on pathogens ofcrops seeds, fruits or vegetables was studied and the main factors influencing theantimicrobial activity of chitooligosaccharides were also investigated. It was foundthat chitooligosaccharides from housefly larvae had wide spectrum fungistasis. It canstrongly inhibit the development of 31 kinds of plant pathogenic fungi such as corticiumrolfsii Saccardo. The results indicated that the degree of deacelylation (DD) or theaverage molecular weight (MW) of chitooligosaccharides were related to the antimicrobialactivity. The antimicrobial activity increased with the rising of DD or the declining ofMW. Pot culture results showed that chitooligosaccharide could enhance the rate ofgermination and emergence of the seeds of maize, wheat and cotton. Chitooligosaccharidehad certain effect on corn southern leaf blight caused by Helminthosporium maydis. 相似文献
17.
套袋对两个苹果品种果实香气成分的影响 总被引:1,自引:0,他引:1
为了解套袋对苹果品种新富1号(Malus domestica Borkh.cv.Xinfu No.1)、长富2号(M.domestica cv.Fuji Nagafu No.2)果实香气成分的影响。利用顶空固相微萃取和气相色谱-质谱联用技术,分别测定了套袋后2个苹果品种的香气成分。结果表明,2个富士苹果品种果实香气成分均以酯类和醇类化合物为主。在酯类化合物相对含量上,未套袋果实套袋果实;在醇类化合物相对含量上,套袋果实未套袋果实。新富1号果实香气成分以乙酸乙酯、乙酸丁酯、2-甲基乙酸丁酯、丁酸乙酯、乙酸己酯为主,长富2号果实香气成分以2-甲基乙酸丁酯、乙酸己酯、正戊酸己酯、2-甲基-1-丁醇、丁酸乙酯、丁酸丙酯、乙酸丁酯、2-甲基丁酸乙酯、丙酸乙酯为主,2个苹果品种的果实主要香气成分基本一致。不过套袋果实乙酸酯型香气成分相对含量均低于未套袋果实。 相似文献
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采用沙门氏菌以针刺法诱导家蝇三日龄幼虫,提取诱导后培养24 h的家蝇幼虫总RNA,进一步分离、纯化其mRNA,运用SMART技术构建家蝇幼虫cDNA文库.结果表明:原始文库的滴度为1.55 × 106 pfu/mL,原始文库重组宰为99.5%,文库扩增后滴度达1.27 × 10 pfu/mL.从扩增文库随机挑取10个噬菌斑克隆进行PCR扩增鉴定,结果显示所选的lO个噬菌体克隆均合有重组的cDNA,插入片段大小为400~1 500 bp. 相似文献
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【目的】了解苹果果实L-半乳糖-1-磷酸磷酸酶(L-galactose-1-phosphate phosphatase, GPP)基因的特性,探索苹果GPP基因表达特性及其与抗坏血酸(ascorbic acid,AsA)水平的关系。【方法】通过RT-PCR从苹果果实中克隆GPP 全长 cDNA,分析其序列特征,进行原核表达,制备GPP特异抗体,分析GPP mRNA及其蛋白表达水平与苹果不同组织AsA的关系。【结果】从‘嘎啦’苹果果实中克隆的GPP cDNA(GenBank登录号为 FJ752240)包含的最大开放阅读框(open reading frame,ORF)为813 bp,编码270个氨基酸残基,预测分子量为29 kD,该基因与其它植物报道的GPP基因具有较高的相似性,但与肌醇-1-磷酸磷酸酶基因差异较大。构建的pET-32a(+)-GPP载体在大肠杆菌BL21(E. coli BL21)中异源表达后,获得主要以包涵体存在约50 kD的融合蛋白GPP-His(His约21 kD)。以该蛋白制备抗体,与重组蛋白的Western杂交表明该抗体能与GPP发生特异反应。对苹果可溶性蛋白杂交显示,苹果体内GPP蛋白约33 kD。在苹果不同组织中,GPP mRNA与蛋白质的相对表达水平与AsA含量存在明显的一致性。【结论】以单体形式存在的苹果GPP蛋白具有翻译后修饰特性,且该基因的表达在苹果AsA合成调控中可能起重要作用。 相似文献
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