植物多肽激素研究概况

目前发现的植物多肽多达9种.基于配基-受体的胞间互作模式,目前公认的植物多肽激素包括4种:系统素(Systemin)、植物硫肽激素(Phytosulfokine)、SCR/SP11和CLV3,分别参与了植食性昆虫防御反应、细胞增殖、自交不亲和的识别,以及茎分生组织干细胞分裂与分化平衡的维持.本文对四种植物多肽激素基因家族的研究进展做了较为详尽的综述,并结合本试验室的研究进展做了展望.     

植物中的“多肽激素”

植物激素是指在植物体的某一组织内合成后、转运到作用部位并对生长发育起调节作用的一类微量有机物质。目前公认的植物激素有５大类,即生长素类、细胞分裂素类、赤霉素类、脱落酸和乙烯。此外,油菜素内酯类、多胺类也被认为是新型的植物激素。在化学结构上,上述几类植物激素都不是蛋白质或多肽。但近年来,在植物体内相继发现了一些具有调节植物生理过程和传递细胞信号功能的活性多肽,称其为“多肽激素”,本文简要介绍以下４种。１　系统素系统素（ｓｙｓｔｅｍｉｎ）是从受伤的番茄叶片中分离的一种由１８个氨基酸组成的多肽,它是植…     

植物多肽激素

近几年研究表明,植物体内存在类似动物和酵母的多肽信号分子,调控植物生长发育以及调节植物对环境的响应。本文介绍了植物中的系统素,RALF,ENOD40,PSK,SCR,SLV3的特点和功能研究进展。     

高等植物中的多肽激素

高等植物的第一个多肽激素(系统素)发现已经有10多年的历史。到目前为止, 被普遍认可的植物多肽激素有4种: 系统素、PSK、CLV3和SCR, 分别参与了植物的防御反应、细胞的分裂、茎端生长点干细胞数目维持和花粉-柱头的识别过程。这些小分子多肽化合物以配基的形式与细胞膜表面的受体激酶相互作用, 从而实现细胞之间的信号交流。本文对这4种多肽激素及其相应受体的研究进展做了简要评述, 并着重介绍当前研究比较热门的CLV3多肽, 最后对相关领域的发展前景进行探讨。     

高等植物中的多肽激素

高等植物的第一个多肽激素（系统素）发现已经有10多年的历史。到目前为止,被普遍认可的植物多肽激素有4种：系统素、PSK、CLV3和SCR,分别参与了植物的防御反应、细胞的分裂、茎端生长点干细胞数目维持和花粉．柱头的识别过程。这些小分子多肽化合物以配基的形式与细胞膜表面的受体激酶相互作用,从而实现细胞之间的信号交流。本文对这4种多肽激素及其相应受体的研究进展做了简要评述,并着重介绍当前研究比较热门的CLV3多肽,最后对相关领域的发展前景进行探讨。     

植物多肽信号分子的特点和功能

近几年研究表明,植物体内存在类似动物和酵母的多肽信号分子,调控植物生长发育以及对环境的响应.介绍了植物中的系统素、迅速碱化因子(RALF)、早期结瘤蛋白40(ENOD40)、植物磺化激动素(PSK)、S位点富含半胱胺酸蛋白(SCR)、CLV3以及相应受体的特点和功能研究进展,并且对多肽信号在植物中的作用及其应用前景进行了探讨.     

植物肽类生长因子--植物硫肽激素-α

植物硫肽激素α(phytosulfokine-α,PSK-α)是一个硫酸酯化的五肽,最初是从石刁柏叶肉细胞培养物的条件培养基中分离到的.它是在植物中发现的第一个肽类生长因子,在很低浓度下就能强烈地刺激低密度培养的植物细胞的增殖.此外,它还能促进植物细胞分化、器官发生和体细胞胚发生.由于它有分布的广泛性和极低的作用浓度,因此越来越受到人们的关注.该文介绍PSK-α的发现、生理功能、基因的结构特点、前体的结构与加工、基因转化与表达、受体以及研究前景.     

植物多肽生长因子PSK的特性与功能研究进展

植物硫化激动素(PSK)是近年来发现的一种新型的植物多肽生长调节物质,具有十分广泛的生物活性和作用.本文从PSK的发现及其结构与功能之间的关系、生理作用、PSK的生物合成和感受以及其与植物非肽激素的关系等方面综述了其研究进展,并对其研究方法及其应用前景进行了探讨.     

新型植物生长调节物质——激素性多肽的研究进展

多肽是生物体内一种非常重要的物质,它以信号的形式调控着生物的生活周期。在动物、细菌、真菌上作为激素、信息素和生长因子已进行了广泛的研究。然而,在植物上1991年才首次报道名叫系统素的伤害信号物质的内生多肽。最近,已从植物中分离出多种肽性植物生长调节因子。本文简要介绍系统素、早期结瘤素、植物硫素、豆胰岛索等四种激素性多肽的发现与分离,以及其结构与生理作用。     

昆虫保幼激素受体的研究与应用进展

保幼激素(juvenile hormone, JH)是昆虫内分泌系统中的关键激素之一,对昆虫生长发育、变态、繁殖起着重要的调控作用。近年来有关JH的分子作用机制取得了极大的进展,主要得益于JH受体的鉴定,大量研究表明JH可通过胞内受体和膜受体两个途径来发挥生理调控功能。本文将从JH胞内受体Met的发现及鉴定、Met转录活性的调控因素、Met功能研究进展,以及Met作为JH受体在JH激动剂及拮抗剂筛选中的应用等方面对JH胞内受体的研究进展进行重点阐述;同时综述了有关JH膜受体的信号通路以及膜受体与核受体的互作等方面的研究进展。     

Peptide signals and their receptors in higher plants

At least four peptides play a vital role in plant cell–cell communication by means of their specific receptors. Two of these receptors have been identified as receptor kinases, which form a large family of receptor molecules in plants. These findings highlight the significance of receptor-mediated peptide signaling in various physiological events in plants, and predict the existence of further peptide-signal-interacting receptor kinases. Some candidates have been found in plant genomes. Here, we outline recent progress and future challenges in the signaling peptide analysis, which began with systemin, phytosulfokine, CLAVATA3 and S-locus cysteine-rich protein (also called S-locus protein 11).     

Plant Peptide Hormones

Russian Journal of Plant Physiology - In addition to classic phytohormones, such as auxin, cytokinin, ethylene, gibberellin, and abscisic acid, plant peptide hormones are also involved in various...     

Peptide Hormones in Medicine: A 100-Year History

Russian Journal of Bioorganic Chemistry - This review is devoted to the 100-year history of the investigation of peptide hormones and the creation of drugs on their basis, starting from the insulin...     

植物多肽信号分子CLE家族

动物中存在众多多肽信号分子,它们在信号转导方面发挥重要作用。近几年,对植物中多肽信号分子的研究取得了重大突破,它们积极参与调控植物生长发育的众多过程,同时也表明多肽信号分子在细胞之间的"交流"过程中发挥作用在进化上是保守的。CLE(CLAVATA3/EMBRYO SURROUNDING REGION)家族是目前植物领域研究较热的多肽信号分子家族,通过对拟南芥CLV3和百日草TDIF等CLE多肽信号分子的研究发现,CLE蛋白在成为有功能活性的信号分子之前,存在翻译后蛋白剪切和修饰的过程,这方面与动物中多肽信使的成熟过程相似。对CLE家族成员的分子特征、生物学功能、翻译后的加工修饰和研究中出现的问题进行综述,并对本领域未来的发展方向作出展望。     

Evolutionary Sequence Modeling for Discovery of Peptide Hormones

There are currently a large number of “orphan” G-protein-coupled receptors (GPCRs) whose endogenous ligands (peptide hormones) are unknown. Identification of these peptide hormones is a difficult and important problem. We describe a computational framework that models spatial structure along the genomic sequence simultaneously with the temporal evolutionary path structure across species and show how such models can be used to discover new functional molecules, in particular peptide hormones, via cross-genomic sequence comparisons. The computational framework incorporates a priori high-level knowledge of structural and evolutionary constraints into a hierarchical grammar of evolutionary probabilistic models. This computational method was used for identifying novel prohormones and the processed peptide sites by producing sequence alignments across many species at the functional-element level. Experimental results with an initial implementation of the algorithm were used to identify potential prohormones by comparing the human and non-human proteins in the Swiss-Prot database of known annotated proteins. In this proof of concept, we identified 45 out of 54 prohormones with only 44 false positives. The comparison of known and hypothetical human and mouse proteins resulted in the identification of a novel putative prohormone with at least four potential neuropeptides. Finally, in order to validate the computational methodology, we present the basic molecular biological characterization of the novel putative peptide hormone, including its identification and regional localization in the brain. This species comparison, HMM-based computational approach succeeded in identifying a previously undiscovered neuropeptide from whole genome protein sequences. This novel putative peptide hormone is found in discreet brain regions as well as other organs. The success of this approach will have a great impact on our understanding of GPCRs and associated pathways and help to identify new targets for drug development.     

Brain, Gut and Skin Peptide Hormones in Lower Vertebrates

Understanding of peptide hormone evolution rests primarily onstructural information, either direct or inferred. We summarizestudies of fishes and amphibians to provide initial informationwithin the vertebrate lineage for selected peptides which exhibitvarying structural heterogeneity. For these peptides, thyrotropin-releasinghormone, somatostatin, luteinizing hormone-releasing hormoneand cholecystokinin related peptides manifest increasing diversification.Members of these peptide families are found distributed amonga variety of tissues (e.g., brain, gut, skin, retina, sympatheticnervous system), yet the number of genes encoding for individualtypes of peptides is presently uncertain. We emphasize the needfor additional structural information, for a more thorough anddiverse taxonomic investigation within the vertebrate lineage,and for specification of those genetic elements which ultimatelydetermine evolutionary opportunities for peptide evolution.     

A New Method of Iodine Labelling of Peptide Hormones

Abstract

Usually peptide hormones and related compounds are radioactively labelled with iodine on tyrosine residues of the peptide. However many peptide hormones do not contain tyrosine or the iodinated tyrosine interferes with the biological properties. In order to circumvent these and other problems, a general method is proposed which allows the introduction of iodine into the para-position of phenylalanine with a modified Sandmeyer procedure. This last-step modification together with HPLC purification permits the obtention of carrier-free and metabolically stable labelled products with maximal specific activity possible. The model has been carried out on several peptide-models like angiotensin II, endorphine and head activator peptide.