高级植物生理课件绪论.ppt

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1、高级植物生理学,主讲人:毛自朝 Tel:5227732(O) 5225102(H) Cell phone :13114297551,You are welcome to the advanced plant physiology!,绪论 第一章 植物细胞及细胞壁 第二章 植物细胞信号传导 第三章 植物的光合作用 第四章 植物的氮硫代谢 第五章 植物的钾代谢 第六章 植物的磷代谢 第七章 植物的基因工程 第八章 植物激素及其信号传导 第九章 植物的生殖与发育 第十章 细胞程序化死亡 第十一章植物的次生代谢 第十二章RNAi,绪论,参考文献,余叔文，汤章城. 植物生理与分子生物学(第二版). 科学

2、出版社，1999，北京。 孙大业，郭艳林，马力耕.细胞信号转导(第三版).科学出版社，2002，北京。 Bob B ,Buchanan, Wilhelm Gruissem , Russell L.Jones Biochemistry Willmitzer认为,ABA 是PIIF,因为伤害使受害叶及相邻叶片的ABA大大增加,直接喷洒ABA于番茄叶片亦可活化pin基因,而缺乏ABA 的番茄突变体,受伤害时,pin 基因的活化能力大大减弱.,3.胞间物理信号 电波的信息传递在高等植物中是普遍存在的。娄成后院士认为： （1）植物为了对环境变化作出反应，既需要专一的化学信息传递，也需要快速的电波传递；

3、（2）植物的电波传递有多种形式：对高敏感植物，外界刺激无需达到伤害程度即可产生动作电波（actionpulse）；中度敏感的植物在伤害刺激条件下产生变异电波(variant pulse)；最不敏感的植物只引起不可传递的局部电位变化，而且植物都有经逆境或剧烈刺激激活的潜在兴奋性；,（3）与动物相似，植物的电波也是质膜极化及透性变化的结果，而且伴随有化学信号的产生（如乙酰胆碱生成）； （4）植物电波长途传递是维管束，短途传递则通过共质体和质外体； （5）各种电波传递都可以产生生理效应。,跨膜信号转换,受体 尤其是质膜外侧受体是胞间信使起作用并转换为胞内信使的首要步骤。ABA、赤霉素及生长素受体位于

4、质膜外侧。植物光敏素是受体之一。光敏素基因已被克隆。激发子（elicitor）及植物毒素（phytotoxin）受体的研究是一个热点。病原或寄主植物细胞壁衍生的激发子，首先作用于寄主细胞表面受体，通过两者的识别与受体激活引起胞内的防御反应,G蛋白（GTP-binding protein） G蛋白的发现使用使Gilman与Rodbell于1994年获诺贝尔医学生理学奖。植物G蛋白研究始于1980年代后期，蛋白印迹法检出的多种G蛋白分子量大都在3137KD之间。用GTP结合试验、免疫反应、分离纯化以及分子生物学和生理试验说明植物中存在G蛋白类似物，但其结构是否与动物G蛋白相同仍有待研究。,细胞内信

5、号,1Ca2+信号 （1）Ca2+信使 不同的胞外刺激引起的胞内Ca2+信号也不仅仅是Ca2+ 的变化，而是有多种Ca2+信号形式，其中多数产生一种短暂（从秒到分量级）、突发而单一的Ca2+峰；而激素GA及细胞分裂常常表现一种适度而持久（分小时）的Ca2+增加，缓慢回落；ABA与植物生长素（Auxin）则常表现为Ca2+振荡（出现多个Ca2+峰）。,植物细胞Ca2+转移系统的研究取得了重要进展。质膜Ca2+泵蛋白已在玉米叶和鸭趾草细胞上纯化并重组入脂质体，并产生ATP依赖的Ca2+吸收。 （2）钙调蛋白 Ca2+信息通过其受体-钙调蛋白的传递信息。已研究的植物钙调蛋白有两种：钙调素（CM）和钙

6、依赖的蛋白激酶。,2双信使 （1）已肯定植物细胞质膜中三种主要的磷脂酰肌醇，即PI、PI（4）P及PI（4、5）P2，其中PI（4、5）P2水解产生的肌醇三磷酸（I（1、4、5）P3）及甘油二脂（DG）两个胞内信使，以及两种信使进一步代谢的产物等。同时整个磷脂酰肌醇代谢的多种酶，如磷酯酶C、质膜上的PI及PI（4）P激酶、DG激酶的多种磷酸酶也已被鉴定出来。 （2）植物细胞中存在IP3/Ca2+传递途径的观点得到更多支持。,第三章植物的氮硫代谢(于虹曼）,Nitrogen and Sulfur often exist in soli at oxidized form ,they must be

7、 reduced before utilized by plant metabolism Few group of plant can obtain NH4+ from N2 by symbiosis nitrogen fixing process Nitrate uptaking by plant is mediated by high and low proton symporters NRT1 and NRT2 And it was reduced by nitrate reductase and nitrite reductase to amommonium for amino aci

8、d synthesis Sulfur which derived and reduced from sulfate , is essential for life. many enzymes for sulfate reduction and sulfur assimilation in plant has been defined and mechanisms for regulation was revealed,第四章植物钾的代谢,1.钾离子是植物细胞中含量最丰富的阳离子之一。它的功能： K+能促进细胞内酶的活性。细胞内有50多种酶或完全依赖于K+ ，或受K+的激活，如丙酮酸激酶、谷胱合

9、成酶、6-磷酸果糖激酶等能被K+激活。作用方式为：同其他一价阳离子都是通过诱导酶构象的改变，使酶得到活化，从而提高催化反应的速率。在某些情况下K+能增加酶对底物的亲和力。K+对膜结合ATP酶也有激活作用。,2.K+与蛋白质的合成有关。小麦胚芽中分离出的核糖体，合成蛋白质达到最佳速率时，其所需K+浓度为130mM。 3 K+可能参与tRNA与核糖体结合过程中的几个步骤。 4 K+能调节植物体的许多生理功能，如增强植物光合作用，增强植株体内物质合成和转运，提高植物抗性，维持细胞膨压等。,一、转运途径 1 真核生物细胞膜上存在Na+ - K+ ATPase，高亲和K+吸收转运体和组织特异性的K+通道

10、。 2 原核生物中至少有4种功能上独立的K+转运系统。,第五章植物的磷代谢,磷是植物生长发育不可缺少的大量营养元素之一，是植物的重要组成部分，同时又以多种方式参与植物体内各种生理生化过程，对促进植物的生长发育和新陈代谢起重要作用 我国农田中有2/3严重缺磷。原因： 被酸性土壤中的铁铝氧化物及石灰性土壤中的碳酸钙化合物固定，成为难被利用的固态磷。如石灰性土壤中磷肥当季利用率一般只有10左右。-土壤磷的遗传学缺乏。实际上，酸性红黄壤与石灰性土壤中总磷一般比有效磷高几百倍。 土壤中的总磷很低土壤学缺磷（本质缺磷）。 高亲和磷酸盐吸收转运体基因及表达 分离到的基因 AtPT1、AtPT2、PHT1、P

11、HT2、PHT3、pht1。其中前两者是最早分离到的高亲和磷酸盐吸收转运体基因。,第六章光合作用（海梅荣）,The overall process of plant, algae ,and prokaryotes directly using light as energy to synthesize organic chemicals In eukaryotic organism photosynthesis is occurred in chloroplast and its is composed of “light” and “dark” reaction Light reaction

12、 involved photosynthetic pigments ,photosynthetic proton transporter chain and ATP synthesis machinery Dark reaction is process involving reduction CO2 to carbohydrates For surviving plant developed C3 C4 and CAM pathways,Photosynthesis,H2O,CO2,O2,C6H12O6,Light Reaction,Dark Reaction,Light is Adsorb

13、ed By Chlorophyll,Which splits water,Chloroplast,ATP and NADPH2,ADP NADP,Calvin Cycle,Energy,Used Energy and is recycled.,+,+, ,第七章植物基因工程,Transgenic plants have potential to impact many areas, including our food supply and our healthcare system and basic research There is no doubt that the technolog

14、y works It is essential that proper testing of all products be carried out prior to commercialization. Popular transformation method is Agrobacterium tumefacis mediate method and its mechanisms,Genes and Proteins,Restriction enzymes,As biological scissors,“Gene Gun” Technique,Gene gun,Electroporatio

15、n Technique,Power supply,Plant Expression Vector Mono Vector System Two component Vector system,Genes =the coding system for instructions A gene =is a segment of DNA,Guanine (G),Cytosine (C),Adenine (A),Thymine (T),bases,DNA,DNA and Genes,gene,Restriction enzymes,As biological scissors,Next Generati

16、on of Transgenic Crops,Plant-based vaccines Enhanced nutritional content Functional foods and phytoceuticals Transgenic plants for phytoremediation Plant-derived plastics and polymers,第八章植物激素及其信号传导,Biosynthesis ,catabolic and conjugated pathway of hormone for homeostasis of plant hormone pools Facti

17、ons and partial signaling pathway of GAs, CTKs, IAA , ABA , Ethylene, BRs, PAsand JA will be discussed,Comparison between auxin and gibberellin signaling pathway,第九章植物的生殖与发育,Inducing of flower and MADs genes expression Gametes formation and double fertilization Seed development and gene expression,第

18、十章 植物的衰老与细胞程序化死亡,Selective cells tissues and organs are essential for plant development and survival PDC: any process which involving protoplasm,W/O cell wall is eliminate as part of development and adaptive events in life cycle of plant,Senescing cell turn on chlorophyll degrading pathway and unmas

19、king carotenoid and other pigment , protein and nuclear acid are broken down for transporting nitrogen or phosphate for reutilization Plant hormone influences the sequencing process HR is part of PDC and it mechanism and function for preventing pathgens further infection,H2H2 induced ,第十一章：植物的次生代谢,E

20、NERGY,hn,CO2,O2,H2O,“N”,N2,NO2-/NO3-/NH4+,TRACE METALS,Na, Ca, K, Mg Fe, Cu, Co, Mo,Photosynthesis,A TYPICAL PLANT,Glycolysis,bacteria,H2O,(daytime),Respiration,(nighttime),PRIMARY METABOLISM,Primary metabolism comprises the chemical processes that every plant must carry out every day in order to su

21、rvive and reproduce its line.,Photosynthesis Glycolysis Citric Acid Cycle Synthesis of amino acids Transamination Synthesis of proteins and enzymes Synthesis of coenzymes Synthesis of structural materials Duplication of genetic material Reproduction of cells (growth) Absorption of nutrients,SECONDAR

22、Y METABOLISM,Secondary metabolism comprises the chemical processes that are unique to a given plant, and are not universal.,Secondary metabolism is the chemistry that leads to the formation of a natural product.,Sometimes portions of this chemistry are common to a number of different plants or plant

23、 families, but the actual chemical produced (natural product) is usually different in one plant than in another.,Common chemical precursors can lead to different results.,Secondary metabolites (in most cases) do not appear to be necessary to the survival of the plant, but they may give it a competit

24、ive advantage.,CO2 + H2O,Photosynthesis,Glucose,Carbohydrates,GLYCOLYS IS,Acetyl CoA,Citric Acid Cycle,Fatty Acids Lipids,Acetogenins Terpenes Steroids,Building Blocks,Amno Acids,Proteins,synthesis,enzymes,regulation,Nucleic Acids,reproduction,Alkaloids,Phenyl- propanoids,RNA DNA,PRIMARY METABOLISM,

25、SECONDARY METABOLISM,SECONDARY METABOLISM,hn,CO2 + H2O + ATP,Flavonoids,photosynthesis,Glucose (6 carbons),starch,n,glycolysis,phosphoenol pyruvate (PEP) (3 carbons),acetyl- coenzymeA (2 carbons),energy (ATP) + CO2 + H2O,mevalonic acid,terpenes steroids carotenoids,erythrose- 4-phosphate,shikimic ac

26、id,anthanilic acid,phenylalanine tyrosine,tryptophan,oxalo- acetate,lysine ornithine,aspartic acid,nicotinic acid,glutamic acid,NH3,Secondary Metabolites?,Primary Metabolites (PMs) The universal compounds found in all plants: the known sugars, protein amino acids, purines, purimidiness of nucleic ac

27、ids, chlorophylls, etc. Secondary Metabolites (SMs) All other plant chemicals that vary in plant species and also do not appear to have an essential role in metabolism: Alkaloids, terpenoids, phenolics, etc.,Origin Secondary Metabolites are said to have first been a photosynthetic byproduct or chemi

28、cal waste, proving fit those plants creating them. Then evolution did its stuff.,1) According to carbon skeletal type. This was found to be “far too cumbersome for practical use.” 2) According to biogenesis or biosynthetic origin. This is the most widely used system of SM classification.,Using a bio

29、synthetic classification system, largest groups of Secondary Metabolites: Terpenoids Alkaloids and other nitrogen compounds Phenolics,Classification Choices,第十二章 RNAi,Definition History Advancement Mechanism Applications,Why is RNAi important?,Most widely held view is that RNAi evolved to protect th

30、e genome from viruses (or other invading DNAs or RNAs) Recently, very small (micro) RNAs have been discovered in several eukaryotes that regulate developmentally other large RNAs May be a new use for the RNAi mechanism besides defense,Recent applications of RNAi Modulation of HIV-1 replication by RN

31、A interference. Hannon(2002). Potent and specific inhibition of human immunodeficiency virus type 1 replication by RNA interference. An et al.(1999) Selective silencing of viral gene expression in HPV-positive human cervical （颈 ）carcinoma cells treated with siRNA, a primer of RNA interference. Jung

32、et al. 2002. RNA interference in adult mice. Mccaffrey et al.2002 Successful inactivation of endogenous Oct-3/4 and c-mos genes in mouse pre implantation embryos and oocytes using short interfering RNAs. Le Bon et al.2002,Posttranscriptional gene silencing,Promoters active Gene hypermethylated in co

33、ding region Purpose - Viral immunity?,S. Grant (1999),Transcriptional gene silencing (TGS),Posttranscriptional gene silencing (PTGS),This has recently been termed “RNAi”,Promoters silenced Genes hypermethylated in promoter region Purpose - Viral immunity?,RNAi(RNA interference)是近年来发现的在生物体内普遍存在的一种古老的生物学现象，是由dsRNA介导的由特定酶参与的特异性基因沉默现象，它在转录水平、转录后水平和翻译水平上阻断基因的表达。RNAi是真核生物体抵抗外源基因(如病毒基因、转座子、人工转入基因等)入侵的一种保护性反应，它还是生物体在不同时期通过调控基因表达来调节细胞分化的机制。RNAi已成为一种极为有用的使基因失活的工具应用于多方面的研究中。,