NBS-LRR(nucleotide-binding site and leucine-rich-repeat)是植物中最大类抗病基因家族之一。番茄基因组测序完成为全基因组水平上分析NBS-LRR抗病基因家族提供了机遇。利用生物信息学方法对番茄NBS-LRR抗病基因家族成员数目进行鉴定...NBS-LRR(nucleotide-binding site and leucine-rich-repeat)是植物中最大类抗病基因家族之一。番茄基因组测序完成为全基因组水平上分析NBS-LRR抗病基因家族提供了机遇。利用生物信息学方法对番茄NBS-LRR抗病基因家族成员数目进行鉴定,并对其染色体定位和系统发育关系进行了分析。随后,将番茄和马铃薯NBS-LRR抗病基因进行了比较基因组学分析。结果表明:番茄基因组共包括252个NBS-LRR抗病基因,分布于番茄12条染色体上;63.5%的基因成簇存在,大部分为串联重复;系统发育关系分析表明番茄CC-NBS-LRR(CNL)亚家族较其他亚家族扩展程度大;同线性分析发现番茄中共79个NBS-LRR抗病基因与马铃薯基因具有同源关系。结果将为番茄NBS-LRR抗病基因家族的深入研究提供依据,同时也为利用番茄NBS-LRR基因进行基因定位以及相关抗病基因克隆等奠定基础。展开更多
The study of plant diseases is almost as old as agriculture itself. Advancements in molecular biology havegiven us much more insight into the plant immune system and how it detects the many pathogens plantsmay encount...The study of plant diseases is almost as old as agriculture itself. Advancements in molecular biology havegiven us much more insight into the plant immune system and how it detects the many pathogens plantsmay encounter. Members of the primary family of plant resistance (R) proteins, NLRs, contain three distinctdomains, and appear to use several different mechanisms to recognize pathogen effectors and trigger immunity. Understanding the molecular process of NLR recognition and activation has been greatly aided byadvancements in structural studies, with ZAR1 recently becoming the first full-length NLR to be visualized.Genetic and biochemical analysis identified many critical components for NLR activation and homeostasiscontrol. The increased study of helper NLRs has also provided insights into the downstream signaling pathways of NLRs. This review summarizes the progress in the last decades on plant NLR research, focusing onthe mechanistic understanding that has been achieved.展开更多
现代网络技术飞速发展,致使通信网络得到深入研究,而网络的可靠性是评估网络好坏的重要标准之一.在以往研究理论和实践的基础上,根据节点删除法/链路收缩法,分别对节点/链路的重要性进行评估,作适当处理,基于网络固有的拓扑结构,并结合...现代网络技术飞速发展,致使通信网络得到深入研究,而网络的可靠性是评估网络好坏的重要标准之一.在以往研究理论和实践的基础上,根据节点删除法/链路收缩法,分别对节点/链路的重要性进行评估,作适当处理,基于网络固有的拓扑结构,并结合网络传输特性,提出了评估通信网络可靠性的新方法——TNL算法(Combined with the importance of Nodes,Link and Transmission flow).该方法有效地评估了在具有不同网络拓扑结构的通信网络的可靠性,实验证明该方法优于二元决策图法,具有高可靠性.展开更多
Nucleotide-binding leucine-rich repeat (NLR) proteins serve as immune receptors in both plants and animals. To identify components required for NLR-mediated immunity, we designed and carried out a chemical genetics ...Nucleotide-binding leucine-rich repeat (NLR) proteins serve as immune receptors in both plants and animals. To identify components required for NLR-mediated immunity, we designed and carried out a chemical genetics screen to search for small molecules that can alter immune responses in Arabidopsis thaliana. From 13 600 compounds, we identified Ro 8-4304 that was able to specifically suppress the severe autoimmune phenotypes of chs3-2D (chilling sensitive 3, 2D), including the arrested growth morphology and heightened PR (Pathogenesis Related) gene expression. Further, six Ro 8-4304 insensitive mutants were uncovered from the Ro 8-4304-insensitive mutant (rim) screen using a mutagenized chs3-2D popula- tion. Positional cloning revealed thatriml encodes an allele of AtlCIn (I, currents; CI, chloride; n, nucleotide). Genetic and biochemical analysis demonstrated that AtlCIn is in the same protein complex with the meth- ylosome components small nuclear ribonucleoprotein D3b (SmD3b) and protein arginine methyltransferase 5 (PRMT5), which are required for the biogenesis of small nuclear ribonucleoproteins (snRNPs) involved in mRNA splicing. Double mutant analysis revealed that SmD3b is also involved in the sensitivity to Ro 8-4304, and the prmt5-1 chs3-2D double mutant is lethal. Loss of At/C/n, SmD3b, or PRMT5 function results in enhanced disease resistance against the virulent oomycete pathogen Hyaloperonospora arabidopsidis Noco2, suggesting that mRNA splicing plays a previously unknown negative role in plant immunity. The successful implementation of a high-throughput chemical genetic screen and the identification of a small-molecule compound affecting plant immunity indicate that chemical genetics is a powerful tool to study whole-organism plant defense pathways.展开更多
为了获得两类光合作用系统Fenna-Matthews-Olson(FMO)和Phycoerythrin545(PE545)在能量传输过程中的动力学演化,首先通过对Ohmic、Debye和Adolphs and Renger(AR)谱密度进行参量化计算,然后将计算结果应用到TNL(时间非局域)方法中,计算...为了获得两类光合作用系统Fenna-Matthews-Olson(FMO)和Phycoerythrin545(PE545)在能量传输过程中的动力学演化,首先通过对Ohmic、Debye和Adolphs and Renger(AR)谱密度进行参量化计算,然后将计算结果应用到TNL(时间非局域)方法中,计算出FMO和PE545的动力学演化过程.结果表明,Ohmic、Debye和AR谱密度参量化后的结果与原谱密度在足够大的频率范围内吻合,而且对比其他方法计算的FMO和PE545的动力学演化过程,该方法计算得到的结果足够精确,其对满足TNL方法要求的可参量化的谱密度函数的扩展是正确的,可用于光合系统的动力学计算.展开更多
文摘NBS-LRR(nucleotide-binding site and leucine-rich-repeat)是植物中最大类抗病基因家族之一。番茄基因组测序完成为全基因组水平上分析NBS-LRR抗病基因家族提供了机遇。利用生物信息学方法对番茄NBS-LRR抗病基因家族成员数目进行鉴定,并对其染色体定位和系统发育关系进行了分析。随后,将番茄和马铃薯NBS-LRR抗病基因进行了比较基因组学分析。结果表明:番茄基因组共包括252个NBS-LRR抗病基因,分布于番茄12条染色体上;63.5%的基因成簇存在,大部分为串联重复;系统发育关系分析表明番茄CC-NBS-LRR(CNL)亚家族较其他亚家族扩展程度大;同线性分析发现番茄中共79个NBS-LRR抗病基因与马铃薯基因具有同源关系。结果将为番茄NBS-LRR抗病基因家族的深入研究提供依据,同时也为利用番茄NBS-LRR基因进行基因定位以及相关抗病基因克隆等奠定基础。
基金The research of the laboratory is supported by funds from the NSERC-CREATE PRoTECT program,NSERC-Discovery,CFIthe Dewar Cooper memorial funds from the University of British Columbia.S.v.W.is partially funded through the UBC Michael Smith Fellowship and NSERC-CGSM awardsL.T.is partly supported by a CSC scholarship.
文摘The study of plant diseases is almost as old as agriculture itself. Advancements in molecular biology havegiven us much more insight into the plant immune system and how it detects the many pathogens plantsmay encounter. Members of the primary family of plant resistance (R) proteins, NLRs, contain three distinctdomains, and appear to use several different mechanisms to recognize pathogen effectors and trigger immunity. Understanding the molecular process of NLR recognition and activation has been greatly aided byadvancements in structural studies, with ZAR1 recently becoming the first full-length NLR to be visualized.Genetic and biochemical analysis identified many critical components for NLR activation and homeostasiscontrol. The increased study of helper NLRs has also provided insights into the downstream signaling pathways of NLRs. This review summarizes the progress in the last decades on plant NLR research, focusing onthe mechanistic understanding that has been achieved.
文摘现代网络技术飞速发展,致使通信网络得到深入研究,而网络的可靠性是评估网络好坏的重要标准之一.在以往研究理论和实践的基础上,根据节点删除法/链路收缩法,分别对节点/链路的重要性进行评估,作适当处理,基于网络固有的拓扑结构,并结合网络传输特性,提出了评估通信网络可靠性的新方法——TNL算法(Combined with the importance of Nodes,Link and Transmission flow).该方法有效地评估了在具有不同网络拓扑结构的通信网络的可靠性,实验证明该方法优于二元决策图法,具有高可靠性.
文摘Nucleotide-binding leucine-rich repeat (NLR) proteins serve as immune receptors in both plants and animals. To identify components required for NLR-mediated immunity, we designed and carried out a chemical genetics screen to search for small molecules that can alter immune responses in Arabidopsis thaliana. From 13 600 compounds, we identified Ro 8-4304 that was able to specifically suppress the severe autoimmune phenotypes of chs3-2D (chilling sensitive 3, 2D), including the arrested growth morphology and heightened PR (Pathogenesis Related) gene expression. Further, six Ro 8-4304 insensitive mutants were uncovered from the Ro 8-4304-insensitive mutant (rim) screen using a mutagenized chs3-2D popula- tion. Positional cloning revealed thatriml encodes an allele of AtlCIn (I, currents; CI, chloride; n, nucleotide). Genetic and biochemical analysis demonstrated that AtlCIn is in the same protein complex with the meth- ylosome components small nuclear ribonucleoprotein D3b (SmD3b) and protein arginine methyltransferase 5 (PRMT5), which are required for the biogenesis of small nuclear ribonucleoproteins (snRNPs) involved in mRNA splicing. Double mutant analysis revealed that SmD3b is also involved in the sensitivity to Ro 8-4304, and the prmt5-1 chs3-2D double mutant is lethal. Loss of At/C/n, SmD3b, or PRMT5 function results in enhanced disease resistance against the virulent oomycete pathogen Hyaloperonospora arabidopsidis Noco2, suggesting that mRNA splicing plays a previously unknown negative role in plant immunity. The successful implementation of a high-throughput chemical genetic screen and the identification of a small-molecule compound affecting plant immunity indicate that chemical genetics is a powerful tool to study whole-organism plant defense pathways.
文摘为了获得两类光合作用系统Fenna-Matthews-Olson(FMO)和Phycoerythrin545(PE545)在能量传输过程中的动力学演化,首先通过对Ohmic、Debye和Adolphs and Renger(AR)谱密度进行参量化计算,然后将计算结果应用到TNL(时间非局域)方法中,计算出FMO和PE545的动力学演化过程.结果表明,Ohmic、Debye和AR谱密度参量化后的结果与原谱密度在足够大的频率范围内吻合,而且对比其他方法计算的FMO和PE545的动力学演化过程,该方法计算得到的结果足够精确,其对满足TNL方法要求的可参量化的谱密度函数的扩展是正确的,可用于光合系统的动力学计算.