稻米品质调控的分子基础及非生物胁迫对稻米品质的影响

水稻是世界上最重要的粮食作物之一,为全球超过半数人口提供食物来源。近些年来,随着温饱问题的解决,稻米品质日益受到关注。随着现代生物技术和生物信息技术的发展,控制稻米品质的基因相继被克隆并应用于水稻育种。本文综述了稻米品质调控分子机制,并对干旱、低温、高温、盐胁迫对稻米品质的影响进行了概述,以期为改善非生物胁迫下的稻米品质提供参考。     

Toward Understanding Molecular Mechanisms of Abiotic Stress Responses in Rice

Plants have evolved delicate mechanisms to cope with environmental stress. Following exposure to environmental stimuli, extracellular signals are perceived and transmitted through signal transduction cascades. Upon receipt and transmission of the signals, a number of stress-related genes are induced, leading to stress adaptation in plant cells. Rice, which is a critical food grain for a large portion of the world’s population, is frequently impacted by several abiotic stressors, the most important of which are drought, salinity, and cold. Exposure to environmental conditions outside of acceptable tolerance ranges can negatively affect rice growth and production. In this paper, a review of rice responses to abiotic stress is presented, with particular attention to the genes and pathways related to environmental stress tolerance. It is apparent that, while progress has been made in identifying genes involved in stress adaptation, many questions remain. Understanding the mechanisms of stress response in rice is important for all research designed to develop new rice varieties with improved tolerance.     

生物与非生物胁迫下水稻CIPK基因的鉴定分析

类钙调磷酸酶B亚基蛋白(calcineurin B-like proteins,CBL)是植物细胞中重要的Ca2+传感器,必须与蛋白激酶CIPK(CBL-interacting protein kinases)特异性互作才能发挥生物学功能.根据水稻OsCIPK(Oryza sativa CIPK)基因家族的预测序列,从粳稻日本晴(Nipponbare)中克隆了15个OsCIPK基因.基因结构分析表明15个OsCIPK可归为多内含子和少内含子两类,OsCIPK3和OsCIPK24的mRNA存在可变剪接.系统进化树分析显示水稻CIPK家族与拟南芥、杨树来源于同一个祖先.这15个OsCIPK在不同程度上受生物胁迫(白叶枯病)和非生物胁迫(Hg2+、高盐、冷和ABA)的诱导表达;其中,5个基因(OsCIPK1、OsCIPK2、OsCIPK10、OsCIPK11和OsCIPK12)在接种白叶枯病菌后表达显著上调;而4个基因(OsCIPK2、OsCIPK10、OsCIPK11和OsCIPK14)的表达受所有胁迫处理诱导,表明这些基因可能参与多种逆境信号的转导.揭示了CIPK可能在植物的生物和非生物胁迫应答中都具有重要的作用.     

生物与非生物胁迫下水稻CIPK基因的鉴定分析

 类钙调磷酸酶B亚基蛋白（calcineurin B like proteins,CBL）是植物细胞中重要的Ca2+传感器,必须与蛋白激酶CIPK（CBL interacting protein kinases）特异性互作才能发挥生物学功能。根据水稻OsCIPK（Oryza sativa CIPK）基因家族的预测序列,从粳稻日本晴（Nipponbare）中克隆了15个OsCIPK基因。基因结构分析表明15个OsCIPK可归为多内含子和少内含子两类,OsCIPK3和OsCIPK24的mRNA存在可变剪接。系统进化树分析显示水稻CIPK家族与拟南芥、杨树来源于同一个祖先。这15个OsCIPK在不同程度上受生物胁迫（白叶枯病）和非生物胁迫（Hg2+、高盐、冷和ABA）的诱导表达;其中,5个基因（OsCIPK1、OsCIPK2、OsCIPK10、OsCIPK11和OsCIPK12）在接种白叶枯病菌后表达显著上调;而4个基因（OsCIPK2、OsCIPK10、OsCIPK11和OsCIPK14）的表达受所有胁迫处理诱导,表明这些基因可能参与多种逆境信号的转导。揭示了CIPK可能在植物的生物和非生物胁迫应答中都具有重要的作用。     

Defensive Role of Plant Hormones in Advancing Abiotic Stress-Resistant Rice Plants

Consistent climatic perturbations have increased global environmental concerns, especially the impacts of abiotic stresses on crop productivity. Rice is a staple food crop for the majority of the world’s population. Abiotic stresses, including salt, drought, heat, cold and heavy metals, are potential inhibitors of rice growth and yield. Abiotic stresses elicit various acclimation responses that facilitate in stress mitigation. Plant hormones play an important role in mediating the growth and development of rice plants under optimal and stressful environments by activating a multitude of signalling cascades to elicit the rice plant’s adaptive responses. The current review describes the role of plant hormone-mediated abiotic stress tolerance in rice, potential crosstalk between plant hormones involved in rice abiotic stress tolerance and significant advancements in biotechnological initiatives including genetic engineering approach to provide a step forward in making rice resistance to abiotic stress.     

甜椒脉斑驳病毒（PVMV）在海南的发现与检测

2014年在海南辣椒病毒病调查过程中发现了一种疑似病毒感染的辣椒样品,主要表现为叶片黄化、绿斑驳、叶脆易折断,且在田间发生较多。利用马铃薯Y病毒属的简并引物对其叶片总RNA进行RT-PCR检测,并将约1 700 bp目的片段克隆到pMD18-T载体上进行测序和BLAST分析。结果表明：该条带序列（包含部分NIb和部分cp基因）与已收录的甜椒脉斑驳病毒（Pepper veinal mottle virus,PVMV）（GenBank登录号：FM202327）序列相似性最高,达99％。设计cp基因的特异引物,对上述样品进行cp基因扩增并构建以cp基因序列为基础的系统进化树,发现海南辣椒上的PVMV与台湾的PVMV分离物ns1株同源性最高。田间检测结果表明：海南黄灯笼辣椒上PVMV的检出率高达74.07％,说明PVMV可能成为海南辣椒生产上的潜在威胁。     

水稻ABC1基因家族的鉴定及在非生物胁迫下的表达分析

ABC1(Activity of bc1 complex)家族属于蛋白质激酶家族,其成员普遍存在于原核和真核生物中.已有研究表明,几个植物ABC1基因参与非生物胁迫应答.为了解ABC1基因在水稻中的结构和功能,采用生物信息学方法分别在水稻和拟南芥上鉴定出15个和17个ABC1基因,并进行了系统发育和表达分析.结果表明,该家族在单、双子叶植物分离之前就已经发生了分化,其基本特征已经形成;单、双子叶植物分离之后,该家族在水稻和拟南芥中均以物种特异的方式进行了扩增.内含子/外显子结构分析显示多数直系同源基因之间外显子大小接近,而内含子差别较大,水稻含有更多大的内含子;内含子获得是近期伴随水稻ABC1家族进化的重要事件.多序列比对显示,ABC1结构域具有1个保守的氨基酸片段和4个保守的氨基酸残基.在线亚细胞定位预测9个水稻ABC1蛋白定位在叶绿体上.实时定量RT-PCR分析表明,水稻ABC1基因主要在叶片中表达,并且受多种非生物胁迫因素包括H2O2、脱落酸、低温、干旱、黑暗和高盐的调控.说明水稻ABC1家族不仅在逆境胁迫应答中发挥重要作用,可能还与水稻特定的生理过程有关.     

水稻ABC1基因家族的鉴定及在非生物胁迫下的表达分析

 ABC1（Activity of bc1 complex）家族属于蛋白质激酶家族,其成员普遍存在于原核和真核生物中。已有研究表明,几个植物ABC1基因参与非生物胁迫应答。为了解ABC1基因在水稻中的结构和功能,采用生物信息学方法分别在水稻和拟南芥上鉴定出15个和17个ABC1基因,并进行了系统发育和表达分析。结果表明,该家族在单、双子叶植物分离之前就已经发生了分化,其基本特征已经形成;单、双子叶植物分离之后,该家族在水稻和拟南芥中均以物种特异的方式进行了扩增。内含子/外显子结构分析显示多数直系同源基因之间外显子大小接近,而内含子差别较大,水稻含有更多大的内含子;内含子获得是近期伴随水稻ABC1家族进化的重要事件。多序列比对显示,ABC1结构域具有1个保守的氨基酸片段和4个保守的氨基酸残基。在线亚细胞定位预测9个水稻ABC1蛋白定位在叶绿体上。实时定量RT-PCR分析表明,水稻ABC1基因主要在叶片中表达,并且受多种非生物胁迫因素包括H₂O₂、脱落酸、低温、干旱、黑暗和高盐的调控。说明水稻ABC1家族不仅在逆境胁迫应答中发挥重要作用,可能还与水稻特定的生理过程有关。
     

Systematic Identification of Rice ABC1 Gene Family and Its Response to Abiotic Stress

Members of the activity of bc1 complex (ABC1) family are protein kinases that are widely found in prokaryotes and eukaryotes. Previous studies showed that several plant ABC1 genes participated in the abiotic stress response. Here, we present the systematic identification of rice and Arabidopsis ABC1 genes and the expression analysis of rice ABC1 genes. A total of 15 and 17 ABC1 genes from the rice and Arabidopsis genomes, respectively, were identified using a bioinformatics approach. Phylogenetic analyses o...     

Resistances of grasses to two sobemoviruses, cocksfoot mottle and cynosurus mottle

Infection of Dactyls glomerata with cocksfoot mottle virus (Cf MV) and of Cynosurus cristatus with cynosurus mottle virus (CyMV) is frequently lethal. However, varieties of each species differ in the proportion of genotypes which survive, and in the damage suffered by these surviving plains. Infected plants of the CfMV-resistant cocksfoot, cv. Cambria, were generally much more aggressive in the competitive environment of the sward than were infected plants of the susceptible cv. S37. Thus, Cambria populations outyielded comparable populations of S37 by only 7% when healthy, but by 40% when infected with CfMV. A few genotypes in the infected Cambria population apparently recovered from the disease, became virus-free and were immune to further infection Resistance to CyMV in C. cristatus takes the form of resistance to systemic spread. A few symptomless and apparently virus-free tillers grow up from the bases of infected tillers. However, these tillers are susceptible to further infection. It is suggested that, in resistant genotypes, CfMV and CyMV trigger the production of antiviral agent(s) which block or restrict virus replication. There is some evidence that CfMV resistance is virus isolate specific, and this could present problems when breeding for durable resistance.     

First report of Cowpea mild mottle virus in chia (Salvia hispanica)

Chia (Salvia hispanica), a herbaceous plant of Lamiaceae family, has gained popularity due to its high concentrations of health-beneficial Omega-3 fatty acids. Plants showing different virus-like symptoms were observed in the principal chia production areas in Argentina. Some plants exhibited yellowing, mottled and blistering leaves, and others shortened internodes and leaf and stem deformation. The aim of this study was to identify the viruses infecting this crop. Forty symptomatic chia plants were collected from nine production fields in northeastern Argentina. The samples were tested for Alfalfa mosaic virus (AMV), Cowpea mild mottle virus (CPMMV), Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV) and Tospovirus group (I, II and III) by DAS-ELISA, for the genera Potyvirus by PTA-ELISA and for Begomovirus by PCR. CPMMV was detected in three plants with different kind of symptoms. In these plants, feather-like inclusions formed by virions were observed with transmission electron microscopy. ORF2 to ORF6 (2462 nucleotides) from the CPMMV viral genome was amplified by RT-PCR. Nucleotide (nt) sequence of the coat-protein gene (CP – ORF5) of the chia virus isolate was obtained and compared with 31 CPMMV sequences reported in GenBank. Results showed between 75.5% and 99.0% of nt identity, which is above the International Committee on Taxonomy of Viruses criteria for Carlavirus species differentiation. The phylogenetic analysis with the CP gene nt sequences revealed that the CPMMV chia isolate grouped with other CPMMV isolates from other plant species from Brazil, Ghana, India, Puerto Rico, Taiwan and USA, but were separated from four others from India. This is the first report of the presence of CPMMV in chia in the world. Although the other viruses were not detected in this work, it is possible that the different symptoms observed could be produced by a mixture of viruses because CPMMV was found in chia plants with different symptoms.     

番茄斑驳花叶病毒海南分离物全基因组序列分析

本研究采用小RNA深度测序及RT-PCR检测技术鉴定海南省陵水县冬种番茄(圣女果)病株受到烟草花叶病毒属的番茄斑驳花叶病毒(Tomato mottle mosaic virus,ToMMV)侵染。通过机械摩擦接种,将该病原病毒保存于本生烟植株上,命名为番茄斑驳花叶病毒海南分离物(ToMMV-HN)。采用RT-PCR分段扩增获得了该病毒分离物的全基因组序列。测序结果表明,该病毒分离物基因组全长6399 nt,含有4个开放阅读框,编码4种蛋白,与已报道的ToMMV9个分离物核苷酸和编码产物氨基酸序列相似性分别为98.0%～100%和99.2%～100%;与同属的番茄花叶病毒(Tomato mosaic virus,ToMV)、番茄棕色皱果病毒(Tomato brown rugose fruit virus,TBRFV)和烟草花叶病毒(Tobacco mosaic virus,TMV)代表分离物核苷酸序列相似性分别为84.7%、80.7%和79.0%。系统进化分析结果表明,ToMMV-HN与该病毒中国西藏和云南辣椒分离物亲缘关系最近,与美国加州和南卡州番茄分离物次之,与西班牙和巴西番茄分离物亲缘关系相对较远。本研究为我国番茄病毒病诊断和防控,尤其是抗病品种选育提供了基础资料。     

Interactions between Metopolophium festucae cerealium (Hemiptera: Aphididae) and Barley yellow dwarf virus (BYDV-PAV)

Interactions between an invasive aphid, Metopolophium festucae (Theobald) subsp. cerealium, and Barley yellow dwarf virus (BYDV-PAV) were studied under laboratory conditions. M. festucae cerealium is an economic pest of wheat and barley that has recently been found in high population densities in wheat in the Pacific Northwest of the United States. BYDV-PAV is the most prevalent and injurious species of BYDV worldwide and in the Pacific Northwest. Although M. festucae sensu stricto (Theobald 1917) has been reported previously as a vector of some BYDV isolates, there is no confirmed transmission of BYDV by M. festucae cerealium. Two experiments examined the ability of M. festucae cerealium to transmit BYDV-PAV. The first used single aphids caged to indicator plants of a BYDV-susceptible winter wheat cultivar and the second used multiple aphids on each test plant. M. festucae cerealium did not transmit BYDV-PAV in either experiment, whereas transmission by a known BYDV vector, Rhopalosiphum padi L., was consistently high (≥93%). A third experiment compared the intrinsic growth rate, days until first reproduction and daily reproduction by M. festucae cerealium on sham-inoculated and BYDV-PAV-infected wheat, but detected no differences. The findings are reviewed in light published data on M. festucae species, BYDV transmission, and the potential pest status of this new invading aphid.