Progress in quantitative analysis of plant hormones

Plant hormones are small molecular natural products that regulate all plant developmental processes at low concentrations. Quantitative analysis of plant hormones is increasingly important for in-depth study of their biosynthesis,transport,metabolism and molecular regulatory mechanisms. Although plant hormone analysis remains a bottleneck in plant scientific research owing to the trace concentrations and complex components in plant crude extracts,much progress has been achieved in the development of extraction,purification and detection techniques in recent years. Solid phase extraction and chromatography/mass spectrometry have been applied widely for purification and quantitative analysis of plant hormones owing to their high selectivity and sensitivity. Purification methods such as liquid partition and immunoaffinity chromatography,and detection methods including immunoassay and electrochemical analysis,are employed. The advantages and disadvantages of these methods are discussed. In situ,real-time and multi-plant hormone profiling will comprise mainstream techniques for quantitative analyses in future studies on the regulatory mechanisms and crosstalk of plant hormones.     

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。     

水产品中环境雌激素特性及检测技术研究进展

环境雌激素会干扰生物体内雌激素的正常分泌,使生物体的生殖功能或免疫功能出现异常。环境雌激素可以分为合成雌激素、生物源雌激素和环境化学污染物,检测方法主要有气相色谱（GC）法、高效液相色谱（HPLC）法、气相色谱-质谱联用（GC-MS）法、化学发光免疫分析（CLIA）法、分子印迹（MIT）法。目前,我国对环境雌激素的研究...     

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。     

Toward understanding the molecular mechanisms governing plant hormone actions: A brief introduction to the major research program “Molecular mechanisms of plant hormone actions” funded by the national natural science foundation of china (NSFC)

Decades of physiological and molecular studies have demonstrated that plants rely on a diverse set of small molecule hormones to regulate every aspect of their biological processes including development,growth and adaptation.The     

The epigenetic involvement in plant hormone signaling

The biosynthesis and signaling of plant hormones play a critical role in almost all biological processes. It is well-documented that phytohormones cross-talk with each other. Epigenetic mechanisms were suggested to regulate expression of downstream targets in hormone signaling pathways that help implement hormone functions. This new layer of complexities that integrate epigenetic information such as DNA methylation, chromatin remodeling, histone modification, microRNAs and siRNAs with plant hormone signaling and regulations of gene expression, has been gradually revealed. In this short review, the author tries to assemble recent progress to establish a molecular linkage between these two large and momentum research fields and also to help readers digest the literature.     

食品中非法添加物检测及分析技术进展

介绍了国内外食品中非法添加物检测技术的研究进展,并对非法添加物检测的新技术和新方法进行评述,同时概述了前处理新技术等内容.依照不同非法添加物的性质,分光光度法、气相色谱法、气质联用法、液相色谱法、液质、离子色谱法、毛细管电泳等检测方法均有应用.酶联免疫、拉曼光谱和生物传感器等新型分析方法研究较多,有望应用来部分取代复杂的传统分析方法.     

猪胸腺激素肽PT_3的研究

本文报导从猪胸腺素注射剂中,利用聚丙烯酰胺凝胶电泳法,分离精制得猪胸腺激素活性肽PT_3的方法。该肽PT_3经反复聚丙烯酰胺凝胶园盘电泳,呈单一区带。经测定,此肽主要由酸性和中性氨基酸组成。用Sephadex-G-50测定其分子量的结果。E-玫瑰花环法测定,有活性。     

Abolition of the expression of inhibitory guanine nucleotide regulatory protein Gi activity in diabetes

Many cell-surface receptors for hormones appear to exert their effects on target cells by interacting with specific guanine nucleotide binding regulatory proteins (G-proteins) which couple receptors to their second-messenger signal generation systems. A common intracellular second messenger, which is used by many hormones, is cyclic AMP. This is produced by adenylate cyclase, whose activity is controlled by two G-proteins, Gs which mediates stimulatory effects and Gi inhibitory effects on adenylate cyclase activity. In liver, the hormone glucagon increases intracellular cAMP concentrations by activating adenylate cyclase by a Gs-mediated process. This effect of glucagon is antagonised by the hormone insulin, although the molecular mechanism by which insulin elicits its actions is obscure. However, insulin receptors exhibit a tyrosyl kinase activity and appear to interact with G-proteins, perhaps by causing phosphorylation of them. In type I diabetes, circulating insulin levels are abnormally low, giving rise to gross perturbations of metabolism as well as to a variety of complications such as ionic disturbances, neuropathies of the nervous system, respiratory and cardiovascular aberrations and predisposition to infection. We show here that experimentally-induced type I diabetes leads to the loss of expression of Gi in rat liver. As it has been suggested that Gi may couple receptors to K+-channels as well as mediating the inhibition of adenylate cyclase, aberrations in the control of expression of this key regulatory protein in type I diabetes may be expected to lead to pleiotropic effects.     

Determination of both jasmonic acid and methyl jasmonate in plant samples by liquid chromatography tandem mass spectrometry

An efficient method for the simultaneous extraction and quantification of both jasmonic acid (JA) and methyl jasmonate (MeJA) from a single plant sample was developed. Plant tissues were firstly extracted by using 100% cold methanol, then the Sep-pak C₁₈ solid-phase extraction (SPE) cartridges were adopted for the purification of sample extract, and finally JA and MeJA were deter-mined by the liquid chromatography tandem mass spectrometry (LC-MS-MS) system. It was found that the accuracy was improved by using the extra standard for the estimation and correction of JA and MeJA losses in the extraction and purification process. The detection limits for JA and MeJA were 0.03 and 0.075 ng mL⁻¹, respectively, and the average recovery rate of JA and MeJA was 92.48% and 94.30%. The method was found to be reproducible and selective, yielding well isolated and easily detectable peaks for both JA and MeJA and simplifying the time-consuming extraction and purification. High-performance liquid chromatography (HPLC) system was employed as the control detection method for the LC-MS-MS system. The two systems were compared in their specificity and accuracy.     

植物生长调节剂对剑兰继代培养中芽形成的影响

用3种植物生长调节剂对剑兰继代培养中芽形成的影响进行了研究。结果表明：植物生长调节剂对继代芽的增殖有较大的影响,多效唑（PP333）和烯效唑（S3307）分别单独使用时,能显著促进芽增殖的浓度均为2.0 mg/L,而水杨酸（SA）在使用浓度为0.5 mg/L时,对剑兰继代芽增殖具有促进作用。     

激光显微切割技术在植物细胞和分子生物学研究中的应用进展

激光显微切割技术是20世纪90年代后期发展,由现代物理学和生物学相结合的精确取材技术.该技术可以在显微镜下利用微激光束直接从不同的组织(包括活体组织)快速切割、分离和纯化生物体的目标组织、细胞及其组分,用于细胞和分子生物学的研究.笔者结合开展激光显微切割技术研究遇到的问题,从制片技术的改进、基因表达、DNA和蛋白质分析等方面,对激光显徽切割技术在植物细胞和分子生物学研究中的应用进行了综述.     

植物激素对花瓣衰老影响的研究进展

衰老是植物生长发育过程中的一个生物学现象.花瓣的衰老是开花植物有性生殖的一个组成部分.近年来,随着对花瓣衰老的深入研究,许多植物激素被证实参与了花瓣衰老的过程.主要阐述了目前对花瓣衰老的相关认识,以及各类植物激素在花瓣衰老中的调控作用和相关分子机制.     

药用植物松塔的化学成分研究

目的：对松科（Pinaceae）华山松（Pinu sarmandii Franch．）松塔的化学成分进行研究，以期寻找活性成分。方法：松塔的乙醇冷浸提取浸膏，依次用石油醚、氯仿、乙酸乙酯和正丁醇萃取，分别得到石油醚、氯仿、乙酸乙酯和正丁醇的萃取物。氯仿和正丁醇萃取物用正、反相色谱法，MCI、Pharmadex LH-20凝胶柱色谱法和HPLC法分离，分离得到6个化合物。结果：根据理化性质和利用NMR、ESI—MS等波谱技术鉴定化合物结构，鉴定了其中的4个化合物：异海松烷（Ⅰ）；Dehydroabietic acid（Ⅱ）；β-谷甾醇（Ⅲ）；β-胡萝卜苷（Ⅳ）。结论：其中化合物Ⅰ～Ⅱ为首次从该种植物中分离得到。     

昆虫滞育相关激素调节的研究进展 (动物科学)

昆虫的生长发育离不开激素的调节。滞育作为昆虫特殊的发育状态,其特征是代谢活动显著降低,发育停滞。在滞育发育过程中,各类激素通常相互协调形成网络,发挥着重要的调节作用。在神经内分泌系统中,由神经细胞分泌的神经肽类激素通常作为上游调控激素,通过调节下游激素的合成和分泌从而影响昆虫的滞育发育;蜕皮激素和保幼激素作为下游激素参与到神经肽类激素的调控网络中。目前已克隆得到滞育激素-性信息素合成激活肽和促前胸腺激素的基因,并对二者在不同滞育型昆虫中的调节作用进行了深入研究。此外,激素受体的研究将为解释激素之间的相互作用提供重要依据;而通过滞育昆虫体内激素水平的调节将为有害昆虫生物防治提供新的方法。     

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.     

确定激素分泌峰和制定分泌峰重合的方法

许多激素具有阵发性分泌特点,在一系列间隔时间大致相等的血样中激素测值不衡定。引起变异的原因至少有以下三个方面:放射免疫测定批内变异、激素基础水平波动和基础值在较长时间范围内的变化。目前尚无一种有效分析方法适用于处理各种激素分泌范型。PULSAR程序和聚类抽样分析较之其它粗略估计方法能更有效地排除引起变异的因素。确定分泌峰和制定分泌峰重合还倚重于内分泌知识和经验。     

Position in the evolution of reproductive endocrine of amphioxus,Branchiostoma belcheri

This review summarizes the recent discoveries of many authors who found that in amphioxus Hatschek’s pit is capable of synthesizing vertebrate gonadotropin-like substance, and that the content of gonadotropin-releasing hormone in the amphioxus’ body shows a positive correlation with the reproductive cycle, and that the sex steroid hormone exists in gonads. Exogenous hormones could promote gonadal development, maturation and reproductive activity in amphioxus. A possible implication might be that the reproductive activity in amphioxus is regulated by reproductive hormones like vertebrate, indicating the existence of primitive reproductive endocrine regulatory axis, brain vesicle-Hatschek’s pit-gonads axis, as compared with regulatory axis of vertebrate. It will provide a new line for establishing the position of reproductive endocrine evolution in lancelet.