植物抗旱性的分子生物学研究进展

随着现代分子生物学技术的迅速发展,植物生理学的研究也进入了一个崭新阶段,在植物抗性机理的研究方面也是如此。近年来,国内外在植物抗旱的分子生物学机理方面取得了长足的进展。本文主要从５ 个方面对近几年国内外的一些实验研究进行了探讨和评述,即植物在水分胁迫下的渗透调节、体内ＣＯ２ 再循环、激素调节、基因响应、活性氧的产生和清除机制等,并对耐旱性转基因植物的发展前景作了简要展望。     

封面图片说明：2016年度中国生命科学领域十大进展

 植物分枝激素独脚金内脂的感知机制。     

植物分枝的奥秘——植物分枝激素独脚金内酯的感知机制

 植物激素调控植物的繁衍生息,与人类生存环境和农业生产密切相关;阐明植物激素被其受体感知的机制,对于揭示植物生命活动的本质具有重要意义。植物的分枝主要受到独脚金内酯等重要植物激素的精准调控。简要综述了植物激素独脚金内酯的作用机理,特别是该激素被其受体感知的机制方面近年来取得的重要进展：系统阐明了单子叶模式植物/作物水稻、双子叶模式植物拟南芥以及寄生杂草独脚金中独脚金内酯被其受体感知的机制,为作物株型改良和消除寄生杂草提供了重要理论指导;开创性地揭示了该新型“受体-激素”感知机制不同于生物学领域过去百年建立的配体,可逆地结合受体、并循环触发信号传导链的“配体-受体”识别理论,为创立“受体-配体”不可逆识别的新理论奠定了重要基础。     

激素对植物耐盐性影响的研究现状与展望

植物激素对植物生理代谢具有重要的调节作用,激素与植物耐盐性关系一直是植物耐盐机理研究的重要内容,为此就盐分胁迫对植物内源激素合成运输和含量的影响,激素与植物盐胁反应的关系,内源外源提高植物耐盐性的作用机量等总是的研究进展作了介绍,并对激素与植物耐盐关系的进一步研究进行了展望。     

IAA和GA3诱导荠菜CBF途径冷应答相关基因表达的研究

低温、干旱以及高盐条件是植物生长过程中所面临的主要逆境胁迫.植物中的CBF途径已被证实是赋予植物低温抗性的主效途径,近年来备受关注.为了阐明荠菜中CBF途径冷应答相关基因表达与激素诱导之间的相关性,本研究利用RTPCR技术,对2种激素分子生长素(IAA)和赤霉素(GA3)诱导处理的荠菜幼苗中CBF途径抗冷相关基因的转录本进行了半定量分析.结果表明,2种激素分子对荠菜CBF途径冷应答相关基因表达诱导作用有一定的差异.因此认为荠菜CBF途径冷应答相关基因表达不仅具有低温的诱导性,而且也具有激素分子IAA和G     

植物激素调控腋生分生组织发育的研究进展

植物分枝的生长是植物发育的一个标志性生长特征,不仅影响着植物株型的多样化,而且也影响着植物的生产力。植物分枝是由腋生分生组织（Axillary Meristems,AMs）实现的,腋生分生组织分布在每个叶基的腋部,并发育成分枝。因此,腋生分生组织发育分化规律的研究,不仅是植物生长发育的基础问题,而且对植物的实践生产也具有重要的指导意义。近年来,随着植物激素合成、信号途径等突变体被分离、鉴定以及相应基因被克隆,人们在植物激素调控腋生分生组织发育方面有了深入的了解。本文对生长素、细胞分裂素、赤霉素和独角金内酯等植物激素在植物腋生分生组织形成与发育过程中的调控机制进行阐述,认为随着新的检测工具和分析技术的发展,未来应加强环境信号介导下植物激素互作对腋生分生组织发育的研究。     

鸭繁殖性状的分子生理学基础研究进展

本文从肝脏与卵巢中脂肪酸代谢的生理生化机制的研究、繁殖相关激素分泌与调节的控制机制研究、其它生长发育相关生理活性物质的研究三个方面对近年的成果进行了总结.鸭繁殖性状的分子生理学基础研究,有助于我们认识鸭相关生物学的分子调控机理,对鸭繁殖性状的育种有指导意义.     

木本植物响应干旱胁迫的研究现状

为深入了解木本植物响应干旱胁迫的分子机理，本文系统的从木本植物对干旱信号的感知、信号转导到转录调控、生理生化反应以及表型变化等方面总结了木本植物对干旱胁迫可能的响应过程.认为木本植物由于其固着根生的特点，不得不进化出相应的机制来应对不断变化的环境.当遭受干旱胁迫时，木本植物根系细胞膜上的感受器首先感知到土壤水分状态的变化，细胞内的蛋白质和激素调控系统触发相应的干旱适应反应.干旱信号通过细胞间的信号传导路径传递到植物体内的各个部位，主要的信号传导途径包括Ca²⁺信号、激素信号和转录因子调控等.一些关键基因和信号通路，如脱落酸(ABA)信号通路、DREB蛋白家族等也参与调控植物的干旱适应性.木本植物也会发生形态和解剖上的变化来减少水分蒸发和增强根系的吸水能力.本文可为抗旱型木本植物选育提供见解.     

青藏高原特有植物分子谱系地理学研究现状

分子谱系地理学是研究物种或近缘物种遗传谱系地理格局和历史成因机制的一种研究方法.通过重建物种进化历史过程可探讨以往地质事件、地形地貌和气候变化对生物物种形成、分化和扩散的影响.文章通过对近几年来青藏高原特有植物分子谱系地理学研究所取得重要成果的介绍,探讨了高原特有植物谱系地理结构,分析和总结了冰期高原植物微型避难所分布格局、居群各分支分化时间和冰期后回迁和扩散模式等.这些研究结果表明,青藏高原不同植物物种具有不同的冰期避难所分布格局和历史扩散特征.     

植物雄性不育机制探究

本文从环境和遗传两个方面探究了植物雄性不育机制 ,首先阐述了营养、温度、光周期及绒毡层发育状况等因素对植物雄性不育的影响 ,并在基因水平上详细概述了细胞核雄性不育和细胞质雄性不育的分子机制 .最后简要介绍了利用基因工程构建植物雄性不育株系的方法 ,显示出植物遗传育种工作的广阔前景 .     

Strigolactone inhibition of shoot branching

A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence that carotenoid cleavage dioxygenase 8 shoot branching mutants of pea are strigolactone deficient and that strigolactone application restores the wild-type branching phenotype to ccd8 mutants. Moreover, we show that other branching mutants previously characterized as lacking a response to the branching inhibition signal also lack strigolactone response, and are not deficient in strigolactones. These responses are conserved in Arabidopsis. In agreement with the expected properties of the hormonal signal, exogenous strigolactone can be transported in shoots and act at low concentrations. We suggest that endogenous strigolactones or related compounds inhibit shoot branching in plants. Furthermore, ccd8 mutants demonstrate the diverse effects of strigolactones in shoot branching, mycorrhizal symbiosis and parasitic weed interaction.     

Inhibition of shoot branching by new terpenoid plant hormones

Shoot branching is a major determinant of plant architecture and is highly regulated by endogenous and environmental cues. Two classes of hormones, auxin and cytokinin, have long been known to have an important involvement in controlling shoot branching. Previous studies using a series of mutants with enhanced shoot branching suggested the existence of a third class of hormone(s) that is derived from carotenoids, but its chemical identity has been unknown. Here we show that levels of strigolactones, a group of terpenoid lactones, are significantly reduced in some of the branching mutants. Furthermore, application of strigolactones inhibits shoot branching in these mutants. Strigolactones were previously found in root exudates acting as communication chemicals with parasitic weeds and symbiotic arbuscular mycorrhizal fungi. Thus, we propose that strigolactones act as a new hormone class-or their biosynthetic precursors-in regulating above-ground plant architecture, and also have a function in underground communication with other neighbouring organisms.     

植物基因工程疫苗研究进展

可口服免疫(oral immunization)绿色疫苗(green vaccine)研究是植物基因工程与分子医学相结合而发展起来的新的研究方向．对当前植物基因工程疫苗的研究方法、疫苗的作用机理进行介绍,总结近10年来国内外植物基因工程疫苗研究进展,并对未来发展方向作出展望．     

生菜遗传转化受体系统的建立及鲑鱼降钙素基因的导入

以散叶生菜大速生(Lactuca sativa var.capatata L.)为试材，以MS为基本培养基。采用不同激素配比，确定生菜高效诱芽培养基为MS 0．1 mg／L6-BA 0．05mg／LNAA；抗生素敏感性试验表明，筛选培养基中适宜的卡那霉素选择压为75mg／L，抑菌剂羧苄青霉素的适宜质量浓度为300mg／L；通过根癌农杆菌介导的叶盘法将鲑鱼降钙素(sCT)基因转入大速生散叶生菜，PCR检测转化率达25．4％。     

Control of phyllotaxy by the cytokinin-inducible response regulator homologue ABPHYL1

Phyllotaxy describes the geometric pattern of leaves and flowers, and has intrigued botanists and mathematicians for centuries. How these patterns are initiated is poorly understood, and this is partly due to the paucity of mutants. Signalling by the plant hormone auxin appears to determine the site of leaf initiation; however, this observation does not explain how distinct patterns of phyllotaxy are initiated. abphyl1 (abph1) mutants of maize initiate leaves in a decussate pattern (that is, paired at 180 degrees), in contrast to the alternating or distichous phyllotaxy observed in wild-type maize and other grasses. Here we show that ABPH1 is homologous to two-component response regulators and is induced by the plant hormone cytokinin. ABPH1 is expressed in the embryonic shoot apical meristem, and its spatial expression pattern changes rapidly with cytokinin treatment. We propose that ABPH1 controls phyllotactic patterning by negatively regulating the cytokinin-induced expansion of the shoot meristem, thereby limiting the space available for primordium initiation at the apex.     

新型分子生物学技术在花卉定向育种中的应用进展

分子生物学技术可以提高花卉定向育种的效率和精准度,其中转基因技术是目前应用最广泛的花卉定向育种技术,基因编辑和高通量测序技术是近年来发展迅速的分子生物学技术。基于国内外研究现状,阐述了转基因和基因编辑技术在花色、花香、株型和抗性育种中的应用,以及高通量测序技术在花卉目标性状调控的分子机制研究、基因定位、分子标记开发方面助力花卉育种的研究进展。提出了利用新型分子生物学技术加快花卉定向育种进程的研究方向与建议,以期为定向培育出具有新奇花色、花香、花型、抗性的观赏植物新品种提供参考。     

Control of tillering in rice

Tillering in rice (Oryza sativa L.) is an important agronomic trait for grain production, and also a model system for the study of branching in monocotyledonous plants. Rice tiller is a specialized grain-bearing branch that is formed on the unelongated basal internode and grows independently of the mother stem (culm) by means of its own adventitious roots. Rice tillering occurs in a two-stage process: the formation of an axillary bud at each leaf axil and its subsequent outgrowth. Although the morphology and histology and some mutants of rice tillering have been well described, the molecular mechanism of rice tillering remains to be elucidated. Here we report the isolation and characterization of MONOCULM 1 (MOC1), a gene that is important in the control of rice tillering. The moc1 mutant plants have only a main culm without any tillers owing to a defect in the formation of tiller buds. MOC1 encodes a putative GRAS family nuclear protein that is expressed mainly in the axillary buds and functions to initiate axillary buds and to promote their outgrowth.