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1.
早在十九世纪中叶,植物解剖学家曾陆续报道过南瓜属(Cucurbita)韧皮部筛分子的筛板上累积有粘液堵塞物(Slime plugs),这种粘液质常穿越筛孔形成粘液索在筛分子之间纵向连续,并推测它可能与韧皮部中有机物的长距离运输有关(Hartig 1854,Ngeli 1861,Fischer 1884、1885,Wilhelm1880)。二十世纪六十年代,随着电子显微镜的  相似文献   

2.
高等植物中的收缩蛋白   总被引:6,自引:0,他引:6  
动物肌肉的收縮已經証明是由一种收縮蛋白——肌动球蛋白与ATP相互作用引起的。动物細胞的运动、鞭毛运动、变形虫运动等也存在着类似肌肉收縮的机制。后来Loewy,Tso等及中島宏通在低等植物粘菌(Myxomycete)的原貭团(Plasmodium)中发現一种对ATP敏感的蛋白质,具有类似肌动球蛋白的性质,Tso等命名为粘菌肌球  相似文献   

3.
高等植物的细胞壁中有一种富含羟脯氨酸的糖蛋白,称为伸展蛋白。其核心蛋白质具有高度重复序列的结构;次级结构为ppⅡ螺旋;它们在细胞质中合成,由高尔基体分泌到细胞壁内组装。作为细胞壁的结构成份,它们的主要功能是调控壁的伸展,并可能在防御反应和形态发生的调节方面起作用。  相似文献   

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高等植物中的蛋白磷酸酶与信号传递途径   总被引:3,自引:0,他引:3  
栾升 《Acta Botanica Sinica》1998,40(10):883-889
蛋白激酶与蛋白磷酸酶在细胞信号传递中起着重要作用。有关高等植物中蛋白激酶的研究工作已经较多,但关于蛋白磷酸酶的研究在以前却未受到足够的重视。本文主要介绍最近有关蛋白磷酸酶在高等植物的信号传递中有重要作用的研究工作。这些与蛋白磷酸酶有关的信号传递途径包括气孔运动调节与脱落酸的信号转导、植物对病原及逆境的响应以及植物发育的调控。这些研究工作清楚地证明,蛋白磷酸酶的功能不仅表现为蛋白激酶功能的逆向平衡机制,而且在许多信号传递过程中蛋白磷酸酶起着主导作用。  相似文献   

6.
高等植物中的乙酰胆碱   总被引:1,自引:1,他引:0  
乙酰胆碱是动物神经传导中重要的神经递质,它在高等植物中也普遍存在,并参与调控某些生理过程。本文对植物乙酸胆碱研究的历史和现状作了介绍。  相似文献   

7.
高等植物中的钼   总被引:14,自引:0,他引:14  
喻敏  王运华 《植物学通报》1999,16(5):547-554
阐述了高等植物缺钼症状,分析了植物体存在的钼酥及钼辅因子的生理生化特性和生理功能及钼辅因子的可能合成途径,并提出以后的研究方向。  相似文献   

8.
高等植物中的钼   总被引:1,自引:0,他引:1  
喻敏  王运华 《植物学报》1999,16(5):547-554
阐述了高等植物缺钼症状,分析了植物体存在的钼酶及钼辅因子的生理生化特性和生理功能及钼辅因子的可能合成途径,并提出以后的研究方向。  相似文献   

9.
高等植物体内酪氨酸蛋白磷酸酶及其功能   总被引:1,自引:1,他引:0  
对高等植物体内酪氨酸蛋白磷酸酶及其功能的研究进展作了简要介绍.  相似文献   

10.
高等植物中的蔗糖载体   总被引:9,自引:2,他引:7  
文章对迄今业已报道和登录的69个蔗糖载体蛋白及其编码基因作了比较分析,并介绍了高等植物蔗糖载体蛋白的系统发生和分类、蔗糖载体蛋白的结构、生物学功能、表达调控模式以及不同亚族蔗糖载体蛋白间的互作模式的研究进展。  相似文献   

11.
高等植物病原相关蛋白   总被引:4,自引:0,他引:4  
在过去的三十年中,人们对诱导系统性抗性——这一普遍存在于高等植物抗病过程中的现象——进行了深入研究。被真菌、细菌或病毒侵染后,植物表现出广泛的、长时间的系统性抗性。在这一过程中,植物细胞壁组成成分发生改变,表达各种病原相关蛋白(PR蛋白),并合成多种植物抗毒素。本文就主要的PR蛋白家族的结构和功能特性,PR蛋白的发现和分类,及PR蛋白的应用作一综述。  相似文献   

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阿拉伯半乳糖蛋白(AGPs)是广泛分布于植物体内的一类富含羟脯氨酸糖蛋白的总称,前人研究结果表明,该类蛋白参与了高等植物生长发育的诸多生物学过程.本文对高等植物AGPs基因家族的分类、AGPs糖基化的氨基酸密码和AGPs鉴定的方法进行了系统的阐述,并对在生殖发育、营养器官发生、植物与环境间的互作等方面AGPs基因的功能研究现状进行了概述,对AGPs研究的前景进行了探讨,希望为今后的相关研究带来启迪.  相似文献   

14.
Physicochemical and functional characteristics of plant protein proteinase inhibitors as antistress biopolymers were studied to determine the mechanisms for plant resistance to phytopathogens and to obtain disease-resistant cereal and leguminous cultures. The activity of trypsin, chymotrypsin, and subtilisin inhibitors varied in monocotyledonous and dicotyledonous cultures. Study varieties of leguminous and cereal cultures were shown to contain endogenous inhibitors specific to proteinases of phytopathogenic fungi Fusarium, Colletotrichum, Helminthosporium, and Botrytis. These inhibitors were characterized by species specificity and variety specificity. Protease inhibitors from buckwheat seeds inhibited proteases of fungal pathogens and suppressed germination of spores and growth of the fungal mycelium. Our results suggest that proteinaceous inhibitors of proteinases are involved in the protective reaction of plants under stress conditions.__________Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 4, 2005, pp. 392–396.Original Russian Text Copyright © 2005 by Dunaevskii, Tsybina, Belyakova, Domash, Sharpio, Zabreiko, Belozerskii.  相似文献   

15.
高等植物钾转运蛋白   总被引:3,自引:0,他引:3  
钾在植物生长发育过程中具有许多重要的作用。以模式植物拟南芥中克隆和鉴定的钾通道和转运体为基础,全面介绍了高等植物中钾转运体系家族,包括Shaker通道、KCO通道、KUP/HAK/KT转运体、HKT转运体和其它转运体。同时,分析了在高等植物中存在多种钾吸收和转运机制的可能原因。  相似文献   

16.
高等植物微管组织中心及其相关蛋白   总被引:1,自引:0,他引:1  
就高等植物微管组织中心及其相关蛋白质的研究进展作了简要介绍.  相似文献   

17.
Linker Histones and HMG1 Proteins of Higher Plants   总被引:1,自引:0,他引:1  
Abstract: Linker histones and the proteins belonging to the high mobility group 1 (HMG1) family are the most abundant proteins associated with the internucleosomal linker DNA in eukaryotic chromatin. Despite their relative abundance, there are indications that they may be involved in specific developmental pathways. In higher plants, a variety of these chromosomal proteins has been identified and characterized. In this report, we give an overview of the present knowledge about these two protein families, and discuss their likely functions in plants.  相似文献   

18.
In a previous communication (Kuo 1964), it was shown by histochemical means that the phloem of cucurbit, as compared with the ground parenchyma, is particularly rich in adenosine triphosphatase (ATPase). A concurrent research by Yen et al. (1965) has succeeded in actually extracting from the vascular bundle of tobacco a crude protein fraction which not only possesses high ATPase activity, but also exhibits viscosity changes on addition of ATP or AMP. Such properties have been known to be characteristic of the contractile proteins constituting the muscle in animals. Although little is known about the actual role played in food transport by the living tissues in phloem, evidence has been accumulating that the active participation of the protoplasm in the phloem is necessary to facilitate sap movement. All these results have tempted us to think that higher plants, just like animals, also derive the energy required for performing mechanical work directly from ATP through the mediation of the contractile protein which is the ATPase itself. Accordingly, the present investigation is engaged in further histochemical observations to locate more precisely ATPase in the sieve element and to map out the distribution of the enzyme in various motor organs of higher plants, with the purpose in mind to see whether the map of enzyme distribution in the tissue has anything to do with its peculiar way of movement. 1. Presence of ATPase in the slime body of the functioning sieve element. In the functioning sieve element, high ATPase activity is displayed at the slime body and the connecting strands traversing the pores of the sieve plate (Plate Ⅰ, figs. 2, 3 & 4). However, as the pores of the sieve plate are partially blocked by the callose, the enzyme reaction becomes lessened. If the plate is completely covered by the callose pad, none could be detected. Since the slime body has been claimed by many workers to be pro- teinaceous in nature (cf. Esau 1950), there should be no surprise that it also possesses enzyme activity and contractile action. This seems to indicate that the slime body and the connecting strands are not mere hindrance to the sap flow but may actively participate in propelling the translocation stream. The fact that the intense ATPase reaction is given in the companion cell (Plate I, figs. 1 & 3) is in conformity with the common notion that the cell is actively involved in the normal functioning of phloem. 2. Enzyme distribution in various motor organs of different sensitivity. The ATPase content in the various motor organs (pulvinus, stamen, tendril, etc.) of different sensitivity has been compared histochemically, ranging from. 1) the highly sensitive organs; e.g. the pulvinus of Mimosa pudica (Plate Ⅱ, fig. 5) and of Oxalis piota (Plate Ⅱ, fig. 6), the stamen of Berberis Watsonae (Plate Ⅲ, fig. 10), the young tendril of Cucurbita maxima Duchesne and Vitis vinifera (Plate Ⅲ, figs. 11 & 12); 2) the moderately sensitive organs; e.g. the pulvinus of Sesbania cannabina (Plate Ⅱ, fig. 8); 3) the feebly sensitive or insensitive organs, e.g. the pulvinus of Robinia pseudoacacia (Plate Ⅱ, fig. 7), the stamen of Brassica campestris var. oleifera (Plate Ⅲ, fig. 9). From the results, it can be seen that the higher the sensitivity of the organ, the greater its enzyme activity. In addition to the morphological assymetry which is typical of plant motor organs, there also exists a physiological gradient, as evidenced by the uneven distribution of ATPase, usually being more intense on the more irritable side. The claim made recently by Aimi (1963) and others that the sudden collapse of the pulvinus of Mimosa on stimulation is not a direct result of the loss of turgidity as is generally assumed, but an immediate manifestation of the active vacuolar contraction in the motor cells is supported by the high ATPase content in the motor cells in our investigation.  相似文献   

19.
Tail-anchored (TA) proteins are a class of polypeptides integrated into the membrane by a C-terminally located hydrophobic sequence which are present in all three domains of life. Proteins of this class lack an N-terminal signal peptide and reach their destination within the cell by posttranslational mechanisms. TA proteins perform a variety of essential functions on the cytosolic face of cellular membranes and, in several cases, determine the organelle identity. Some TA proteins insert directly into the lipid bilayer without the help of molecular machinery, suggesting that they may be ancestral proteins able to recruit lipids, contributing to the formation of intracellular compartments during cell evolution. Relevant progress has been made in recent years on the identification of TA protein sorting and the posttranslational translocation machineries. Interestingly, membrane lipid components were also found to be involved in the insertion mechanism. A bioinformatic approach is used to produce a catalogue of putative TA proteins encoded by the Arabidopsis thaliana genome, and intracellular localization is predicted based on features of well-characterized TA proteins. A recent strategy aimed at improving the accumulation of recombinant proteins expressed in transgenic plants is also discussed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

20.
冷害是世界范围内普遍存在的问题。冷驯化是通过低温诱导植物形成抗冷力的过程。冷调节蛋白是植物在冷驯化下产生的特异性蛋白质,与植物的抗冷力密切相关。随着分子生物技术的发展,成为近年来抗冷生理研究的热点之一。本文介绍了植物冷调节蛋白的分布、结构、性质、功能及诱导调控等方面的最新研究进展,并展望了将来的研究方向。  相似文献   

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