马铃薯Y病毒蚜传辅助因子促进马铃薯X病毒长距离运输

采用PCR和定点突变法,对马铃薯Y病毒中国株系（Chyinese strain of potato Ypotyvirus,PVY-C)蚜传辅助成分（helper component proteinase,HC-Pro)基因中心区域的CCCT基序和PTK基序进行定点改造,获得了4种突变体。然后将突变体砍降到植物表达载体pBin438中,所得到的重组体通过根癌土壤杆菌（Agrobacterium tumefaciens(Smith et Townsend)Conn）介导法转了烟草（Nicotiana tabacum L.cv.K326).Southern blotting和Western blotting分析表明4种突变体已经成功整合到烟草的基因组中,并在蛋白水平上得到了表达。马铃薯X病毒（potato X potexvirus,PVX)对转基因烟草的攻毒实验表明,4种突变体均使PVY－C HYC－Prog严重丧失了促进PVX病毒粒子在寄主体内积累和提高PVX致病性的功能,说明CCCT、PTK基序为PVY－C HYC－Pro介导PVX／PVY协生作用所必需。同时证明了HC-Pro具有增强PVX在寄主体内长距离运输的功能。     

马铃薯Y病毒HC-Pro中心区域在病毒协生作用中的主导地位

利用PCR方法获得了马铃薯病毒中国株系（PVY－C）HC－Pro基因的5个缺失突变体,构建了相应的植物表达载体。通过土壤农杆菌(Agrobacterium tumefaciens)介导法转化了烟草品种K326(Nicotina tabacum cv.k326)。PCR和Southern blot分析证明了HC－Pro基因及其缺失突变体已整合到烟草基因组中,Western blot表明它们在转基因烟草中得到了表达。侵染性试验发现HC－Pro中心区域介导转基因烟草中PVC－C和黄瓜花叶病毒（CMV）、PVY－C和马铃薯X病毒（PVX）之间的协生作用,从而明确了PVY－C HC－Pro中心区域为病毒协生作用的功能区域。     

马铃薯Y病毒HC-Pro中心区域在病毒协生作用中的主导地位

利用PCR方法获得了马铃薯病毒中国株系(PVY-C)HC-Pro基因的5个缺失突变体,构建了相应的植物表达载体。通过土壤农杆菌(Agrobacterium tumefaciens)介导法转化了烟草品种K₃₂₆(Nicotina tabacum cv.K₃₂₆)。PCR和Southern blot分析证明了HCPro基因及其缺失突变体已整合到烟草基因组中,Western blot表明它们在转基因烟草中得到了表达。侵染性试验发现HCPro中心区域介导转基因烟草中PVY-C和黄瓜花叶病毒(CMV)、PVYC和马铃薯X病毒(PVX)之间的协生作用,从而明确了PVY-C HC-Pro中心区域为病毒协生作用的功能区域。     

马铃薯Y病毒属病毒HC—Pro蛋白功能研究进展

马铃薯Ｙ病毒属病毒基因组编码的ＨＣ－Ｐｒｏ蛋白（蚜传辅助因子）具有多种功能,在病毒生活中史各个环节中起重要作用。ＨＣ－Ｐｒｏ蛋白具有蛋白酶活性,作为蚜传辅助因子参与病毒蚜传过程,调节病毒中宿主体内的转移,并在病毒复制、宿主症状表达及增强异源病毒复制等方面发挥作用。本文对ＨＣ－Ｐｒｏ蛋白的既定、预测功能作一综述。深入了解ＨＣ－Ｐｒｏ蛋白的功能不仅在理论上有助于明确病毒生活周期,而且在实践上也可根据其     

马铃薯Y病毒组两病毒辅助成分的纯化及其传毒专化性的研究

马铃薯Ｙ病毒组两病毒辅助成分的纯化及其传毒专化性的研究吴云峰（植物病虫害生物学国家重点实验室,中国农业科学院植保所,北京１０００９４）魏宁生（西北农业大学植物保护系,陕西杨陵７１２１００）关键词马铃薯Ｙ病毒组,辅助成分,蚜虫传毒专化性自从１９７１年Ｋ...     

马铃薯Y病毒NIb复制酶基因在转录水平介导的相对广谱抗病性

在大肠杆菌中表达了马铃薯Ｙ病毒中国分离物（ＰＶＹ－Ｃ）复制酶ＮＩｂ基因,并制备了其抗血清。利用ＰＣＲ定点突变方法使ＮＩｂ基因移码－１位,构建了移码－１位ＮＩｂ基因（ＵＮ）的植物表达载体。通过土壤农杆菌（Ａｇｒｏｂａｃｔｅｒｉｕｍ ｔｕｍｅｆａｃｉｅｎｓ ＬＢＡ４４０４）介导转化烟草ＮＣ８９,获得５１株再生植株。对再生植株的分子检测结果表明,转基因烟草中检测到ＵＮ基因相应的ＲＮＡ转录产物,３推测该基     

Resistance to potato virus Y and potato virus X in Solanurn brevidens

Although Solanum brevidens could be infected with potato virus X (PVX), potato virus Y⁰ (PVY⁰) and PVY^N, no symptoms of infection were apparent and tests by double antibody sandwich ELISA, electron microscopy and sap transmission to local lesion test plants indicated that the titres of PVX were less than a tenth of those of PVY⁰ and PVY^N were less than a hundredth of those in infected plants of PDH40, a susceptible dihaploid clone of S. tuberosum cv. Pentland Crown. Furthermore, PVY⁰- and PVY^N- infected leaves of S. brevidens were a poor source of inoculum in aphid transmission tests. The possibility of a common mechanism and genetic basis of resistance to PVY, PVX and potato leaf roll virus in S. brevidens is discussed.     

应用Dot—ELISA检测PVX,PVY和PVS

以ＮＣＭ为固相载体、应用间接ＥＬＩＳＡ法测定了纯化的ＰＶＸ、ＰＶＹ和ＰＶＳ;对接种的烟草,马铃薯块茎的芽、休眠块茎顶端的稀释度ＰＶＸ分别为：１／２０４８０－１／８１９２０、１／５１２０;ＰＶＹ分别为１／８１９２０、１／２０４８０和１／５１２０;ＰＶＳ分别为１／８１９２０－１／３２７６８０、１／２０４８０－１／８１９２０和１／５１２０－１／２０４８０,和Ｃｏｃｋｔａｉｌ－ＥＬＩＳＡ相关,检测ＰＶＸ和     

黑龙江马铃薯Y病毒P1基因的特点北大核心CSCD

【目的】本研究通过对不同PVY分离物基因的测序及分析,从而了解PVY株系的多样性,进而对PVY病毒的分子检测及防治提供重要的资料和参考。【方法】本研究针对黑龙江15个马铃薯Y病毒样品的P1基因进行克隆测序和进化树分析。【结果】经比对分析,样品被分成两组,有10个样品的基因类型高度同源,且相对保守,是本地区的优势群组,无论是与国内其它地区样品比较还是与国外样品比较,其亲缘关系都有一定距离;而另一组中的5个样品的P1基因与本地优势组群有较大差异,且这5个样品间也有一定的差异,并与国内其它地区和国外一些样品的P1基因序列比较接近。通过比对Gen Bank中已上传的序列提供的PVY株系的信息,得知本次试验的P1基因与PVY^(NTN-NW)株系是相似的,且这15个样品与国内其他样品一样都是由PVY^N株系演变而来。【结论】由P1基因分析表明,PVY受环境影响较大,黑龙江10个样品的PVY在长期的进化中产生了具有地方特点的变化,而后来的5个样品说明中国大部分PVY有可能是跟随国外品种资源的引进进入,同时PVY也随国内不同区域间资源交流和种薯调运而传播。     

Potato virus Y NIa protease activity is not sufficient for elicitation of Ry-mediated disease resistance in potato

Ry confers extreme resistance (ER) to all strains of potato virus Y (PVY). In previous work, we have shown that the protease domain of the nuclear inclusion a protease (NIaPro) from PVY is the elicitor of the Ry-mediated resistance and that integrity of the protease active site is required for the elicitation of the resistance response. Two possibilities arise from these results: first, the structure of the active protease has elicitor activity; second, NIa-mediated proteolysis is required to elicit the resistance response. To resolve these possibilities, the NIaPro from PVY was randomly mutagenised and the clones obtained were screened for elicitation of cell death as an indicator of resistance and proteolytic activity. We did not find any mutants that had retained the ability to elicit cell death but had lost protease activity, as measured by processing of the NIa cleavage site in the viral genome. This was consistent with the idea that protease activity is necessary for elicitor activity. However, protease activity was not sufficient because we found three elicitor-defective mutants in which there was a high level of protease activity in this assay.     

Expression of Potato Virus Y Coat Protein Gene in Transgenic Potato

Potato virus Y (PVY) N coat protein (CP) coding sequence was cloned into a plant expression vector pMON316 under the CaMV 35S promoter. Leaf discs of potato (Solanum tuberosum) were used to Agrobacterium-mediated gene transfer. A large number of regenerated putative transgenic plants were obtained based on kanamycin resistance. Using total DNA purified from transgenic plants as templates and two oligonucleotides synthesized from 5' and 3' of the PVY coat protein gene as primers, the authors carried out polymerase chain reaction (PCR) to check the presence of this gene and obtained a 0. 8 kb specific DNA fragment after 35 cycles of amplification. Southern blot indicated that the PCR product was indeed PVY CP gene which had been integrated into the potato genome. Enzyme-linked immunosorbent assay (ELISA) of our transgenic plants showed that CP gene was expressed in at least some transgenic potato plants.     

Transfer of resistance to potato leafroll virus, potato virus Y and potato virus X from Solarium brevidens to S. tuberosum through symmetric and designed asymmetric somatic hybridisation

Resistance to potato leafroll virus (PLRV), potato virus Y (PVY^o) and potato virus X (PVX) was studied in symmetric and asymmetric somatic hybrids produced by electrofusion between Solanum brevidens (2n=2×=24) and dihaploid S. tuberosum (2n=2×=24), and also in regenerants (B-hybrids) derived through protoplast culture from a single somatic hybrid (chromosome number 48). All of the somatic hybrids between 5. brevidens and the two dihaploid lines of potato cv. Pito were extremely resistant to PLRV and PVY^oand moderately resistant to PVX, irrespective of their chromosome number and ploidy level (tetraploid or hexaploid). Most (56%) of the asymmetric hybrids of irradiated S. brevidens and the dihaploid line of potato cv. Pentland Crown (PDH40) had high titres of PVY^osimilar to those of PDH40, whereas the rest of the hybrids had PVY^otitres less than a tenth of those in PDH40. Three B-hybrids had a highly reduced chromosome number (27, 30 and 34), but were however as resistant to PLRV, PVY^oand PVX as 5. brevidens. Two asymmetric hybrids and one B-hybrid were extremely resistant to PLRV but susceptible to both PVY and PVX. The results suggested that resistance to PLRV in 5. brevidens is controlled by a gene or genes different from those controlling resistance to PVY and PVX, and the gene(s) for resistance to PVY and PVX are linked in S. brevidens.