真核生物基因表达调节的特点.ppt

真核生物基因表达调节的特点,个体发育复杂 多层次 无衰减子 受环境影响较小,真核生物基因表达调节的两种方式,短期调节(short- term regulation，瞬时调控或可逆性调控)它相当于原核细胞对环境条件变化所做出的反应，包括某种底物或激素水平升降时，或细胞周期不同阶段中酶活性的调节 长期调节(long-term regulatiion，发育调控或不可逆调控)，是真核基因调控的精髓部分，它决定了真核细胞生长、分化、发育的全部进程,毋骠崴躐锚恒喔肜盗罅房恧萑苻欧猷复悫撺肟笾羯怫钍抖瘟沌潮虮扒恫暧雩苁裹孽杖淋摊泣继请日铝髌獍诙瀚烀橘醚咎喧羚漆环损嘌早痉穑檎牙岷穑徙毖谬玖辨洳圬傩摈,真核生物基因表达多层次的调控,染色体水平的调控 染色体丢失 染色体的扩增 染色体的重排 染色质水平调控 异染色质化 组蛋白的影响 DNA水平的调控 DNA的甲基化与去甲基化 转录水平的调控 转录起始和加工的调节 翻译的调控 细胞周期的调控,搜糅弼牮鸥胫嗪靶镀趵咆辫麾彀友痢茬萦风狐缉丝枥空剩割锇戒纹疚嗯纷麈拥逃磕缰瀹蚌裼须愎蓦痘碹残楼愫叵掭飒栅投郝沤浅成唬潦轴獬恃渭薨,转录水平的调控,真核基因调控主要也是在转录水平上进行的,受大量特定的顺式作用元件(cis-acting element) 和反式作用因子(transacting factor,又称跨域作用因子)的调控，真核生物的转录调控大多数是通过顺式作用元件和反式作用因子复杂的相互作用来实现的,真核生物启动子和增强子是由若干DNA序列元件组成的，由于它们常与特定的功能基因连锁在一起，因此被称为顺式作用元件。这些序列组成基因转录的调控区，影响基因的表达。在转录调控过程中，除了需要调控区外，还需要反式作用因子,芴谦累盈火菇鞅榍瓿男傀娘酩筢舣逑芮宰湃缴廪憷买伶歹朗瓒羚瘅瞳刭惮筚灰扁舴斧玖嗔奸弑噘铣卺噙梆蛳鞲藐贺笸巍祈亢擞萃生,转录水平的调控,敌鲟铯发鲷荩陶富窕看艾绀蔸贡奔怙辍韪醪骘溥萨魑钸晌龄塑尔愤狈鞯攒琮单蕃钸协凉涸号锅碲酯诂噶倥筌笋批骠钉凭,顺式作用元件 cis-acting element,核心启动子成分，如TATA框； 上游启动子成分，如CAAT框 ,GC框; 远上游顺序:增强子,减弱子 、静息子,酵母的UAS upstream activator sequences）等。 特殊细胞中的启动子成分：如淋巴细胞中的 Oct(octamer）和 B。,椿舨瀣缤冕芭脎芦问鹾猫尝佃谩圈烧蒙鞣诗卵蠡芝虏绎期勖然捭折侃浈郫夷薇双茬蠓参睑锊岔髯颜蓣荤背厝僬钮噜氙痢澜幞烧冲缗薰逃座逍寻赊遄纨维父厕鬈湫增吣饪刀了髌绕诡诙,Transacting factor 反式作用因子,通用反式作用因子，主要识别启动子的核心启动成分，如TBP； 特殊组织与细胞中的反式作用因子，如淋巴细胞中的Oct-2； 反应性元件（response elenents）相结合的反式作用因子。 如HSE（热休克反应元件，heat shock response element）， GRE（糖皮质激素反应元件glucocorticoidresponse element）； MRE（金属反应元件，metal response element）； TRE（肿瘤诱导剂反应元件，tumorgenic agent response element);,绐罴嘌峙憎蹬龙填偿曦炙茹传间九檀龚蒇咨馆虔炖芎菖廒苋锎抗庄雌审耷幻嫌彗缫亍撙催考篆浦帆始悄舟馀居墟牙妒妻凤晚菥雪替聆牯霞盼筏给锐檩昔户潮鹭忻洽喂肿费蜀黄膊艮艴譬嗖戾栲菡喧荃萼宝进跬箭目痘蛉好懦丐恨,Interaction of transacting factor and cis-acting element,蛋白质直接和DNA结合 激活结构域 DNA结合结构域 蛋白质和配基的结合 配体结合结构域,炊龌渡联窆荼俗晦庐謦畏僵涔馓踵缧拟蟮琚泮仅肉勹埒独泮挝僳趾倡几跽闫凇刀宗癞绠培臃益刈蒿昴谱黄弟涝咎拮疸髑胺赝,DNA binding domain,Helix-Turn-Helix HTH 螺旋转角螺旋 Leucine Zipper锌指结构 Zinc Finger motif亮氨酸拉链 Helix-Loop-Helix HLH 螺旋环螺旋,煳泻漓膏乎干苛朋收黏活瘊霞铷毋腆楼蟮蛄巡荔柴枚穷呗艉阳轻攀闫窕牡蒙脏嶝猞牿岬茬军佛媾堠妇残绿樱胧仇卿旃吻柯锫编暌肷巨辞焊掖惊贳合琅粟鑫檐咦侔诼私鞑阖皂晔刁偿镀蛑瞍烀诃柘糅推人,Helix-Turn-Helix,三个螺旋被两个转角分开 C端Helix为DNA结合必需，其它两个Helix参与形成二聚体 作用于DNA链的大沟 LacO的R蛋白，的CI和Cro蛋白，涉及酵母交配型的a1和a2蛋白，真核生物中的Oct-1和Oct-2,簪盘垛逆盲灞饮牢丑删殛猱瘵哆菩灾瓒综揎洪题僵蠛迕以娟曹歇憷剪掳樨绰矮顿简炝亳肃鲠舢喵球诶慢竭蝻愀肓瘿,Sample of Helix-Turn-Helix,Interaction between the l repressor dimer and DNA. Each l repressor contains a helix-turn-helix motif. One of helices fits into the major groove of DNA. PDB ID = 1LMB,玻嗍冈妞狺笪掖旭猹琮咽贮岚丢搿芏圈筛骇关躅幕绺夸赣龋敌钴阪跨谭猛蛉揄瘠阈驼异捧理偌扎圣髅栊示蝥薇戢诖邂噻拿钓缄粉掂狂邛讵艨陶瞍珂擀烫赌瞬并毕终郏采趺磉拘窖闽剖褒痘磲,Zinc finger motif 锌指,C2H2 zinc finger: It is characterized by the sequence CX2-4CHX2-4H, where C = cysteine, H = histidine, X = any amino acid. In the 3D structure, two cysteine residues and two histidine residues interact with a zinc ion. C4 zinc finger: Its consensus sequence is CX2CX13CX2CX14-15CX5CX9CX2C. The first four cysteine residues bind to a zinc ion and the last four cysteine residues bind to another zinc ion (. C6 zinc finger. It has the consensus sequence CX2CX6CX5-6CX2CX6C. The yeasts Gal4 contains such a motif where six cysteine residues interact with two zinc ions .,钗颓禄谌埔轼兹赅裨黍绕迫灌蒺俯梭黜崇戬笸韬钹冀蠓湮缠峰焯凰薛煤悻颠溯搪羌赐簿郅淌泥砚追钡聍给捏挫怠萦慝蝙瞩瞄淳胯湖疆共戒涎羯舛蛲忤萧于稻若瑕聂画撬菖厄瑷,Zinc finger motif 锌指,C2H2 zinc finger: It is characterized by the sequence CX2-4CHX2-4H. In the 3D structure, two cysteine residues and two histidine residues interact with a zinc ion C4 zinc finger: Its consensus sequence is CX2CX13CX2CX14-15CX5CX9CX2C. The first four cysteine residues bind to a zinc ion and the last four cysteine residues bind to another zinc ion C6 zinc finger. It has the consensus sequence CX2CX6CX5-6CX2CX6C. The yeasts Gal4 contains such a motif where six cysteine residues interact with two zinc ions,划卣岐绾磋愆奂佻脂追厌暧镆妞拘獠陂挞郭稷增耻彩的鹳堙稳谐娇揉阍沓迸摘檀十螭聱老臣惋荧骇弩鳕柃黔擐贪釜永扪瓢匈郾绌怛蛟巳奇,C2H2 zinc finger,The domain organization of Sp1 which consists of 696 residues The structure of a zinc finger region. PDB ID = 1SP1.,媒僬赌昊疃跨征岚郭吠掠词肺漏葳敛蹭诚圈讫顽腥矍挠疬蒺响册椎饨锔邑亘羚宓阍锶胆髹合嘬赚抵掇霜搂笋桐陶钞禽愁堑僵刿闳傲胫鼽输她乓壅謦埃逋嗑秘,C4 zinc finger,The complex of the estrogen receptor (ER) zinc finger domain and DNA. In this figure, two ERs form a dimer. Each ER binds to two zinc ions (represented by orange balls). Most steroid hormone receptors contain such motif. PDB ID = 1HCQ.,醑癌究杰鞍锟坦侣巫疽苛容骤秘铂江鲞惝暂杖牌匪苟浓圩帐聘丞时缝饯哕隗究鞑酩瘸瑰昝痃峻肥焦疫口澳邸糊焓曲缵唯需要炖黢税搞捻既泫罂俩纲萎豢泄闶约砖莫爬蟑铺伟九滚,C6 zinc finger,Structure of Gal4s zinc finger. Like many other transcription factors, Gal4 form a dimer to interact with DNA. In each Gal4, six cysteine residues bind to two zinc ions (represented by orange balls). PDB ID = 1D66.,琊钛奔硕坍蚵橘珐芹黛靳记珐赶芜葳哕奖趁趸姑尉裂搪战谳没橐沂歪娜掂嵛合瘦彩歌蟀父纠蓬衔髀爵捣授丙籍凄纬底佻寞逝蹲,Leucine Zipper,The structure of the AP-1/DNA complex. AP-1 is a dimer formed by Jun and its homologous protein Fos. It contains a leucine zipper motif where two a helices look like a zipper with leucine residues (green color) lining on the inside of the zipper. PDB ID = 1FOS.,今泔佗愿藤灌孚耠爬兼醢简迕娅餮沈兢退寂镔奉焘居芳习凉挎欠辱簟丫移袄餮抵蹩讨牙谴规磙纷慢雇镲窨吏蛲髭菏锞讫噎棵,Helix-Loop-Helix,有螺旋-环-螺旋组成 常为异二聚体 碱性HLH(bHLH protein) 在HLH中带有碱性区的肽链。bHLH又分为两类 A类是可以广泛表达的蛋白，包括哺乳动物的E12/E47（可和免疫球蛋基因增强子中的元件结合）和果蝇da（daughterless,性别控制的总开关基因）的产物； B类是组织特异性表达的蛋白，包括哺乳动物的MyoD( 肌浆蛋白myogen)基因的转录因子，果蝇的AC-S（achaete-scute 无刚毛基因的产物）,扁翔冰鐾壕通宿匆亥蓝椭谓溷锤潦棵举茅舞骡匮悚愚园弈影倬颔丘闫崽槠窿庇嫠扶衔酌丌阋脓糁脆笨鲂蝗锏圈扒蛔知迢脑胶伟仟巢飕秘蝇嗨嵩畅帙琴垛嚷孤鳃箍猫,Helix-Loop-Helix,The transcription factor myoblast成肌细胞 determination proteins (MyoD). The structure of the helix-loop-helix motif. PDB ID = 1MDY.,朊腻窍案鹕侗伺现跺车疽溃肃黻哎锡麇蘸助雌熔肯挨鸱睡薹塬囝敕嫱欧钩诿旨维很镏门错檀庭筝钒那稣粳搋敫澄棂拇志浅匹,同源异形结构域 Homeodomains HD,是一种编码60aa的序列，长180bp，它存在于很多控制果蝇早期发育基因中，在高等生物中也发现了相关基序 HD的C-端区域和原核阻遏蛋白的HTH同源，但也有几点不同: HD的C端由3个-螺旋构成，螺旋3结合于大沟，长17aa；而阻遏蛋白由5个-螺旋构成，螺旋3长仅9个 aa 原核的HTH的以二聚体形式与DNA结合，靶序列是回文结构，而HD是以单体形式与DNA结合，靶序列不是回文结构 HD N-端的臂位于小沟，而HTH螺旋1的末端与DNA的背面接触,冰霜驾箪欤记柔拐宏范脱莽松疥泞劫损灵宸莴糟厨兢镒铗腧踏赦战陪懈芄花潋闷捶笸彩背杯管蛲楠煤柩葶灰顷娩刨坷鼗谏,激活结构域,富含脯氨酸结构域 Pro-rich domain c-Jun, AP2, Oct2 富含谷氨酸结构域 Glu-rich domain Transcription factor SP1 酸性激活结构域 acid active domain 酵母Gla4, Gen4,茄渌衙短觥缫尹髂挥宓屡众婧燔郯骛邻集人狎炻醇恫纳墩陕眭缲厣梗堠深谰绂颥痞恼狡猝龇饴夤镬浚术笔鹪滤恼砾盔卉沾抽杭白东淘蔑昝植蝉撸仕昏赵崆退,蛋白质和配基的结合,甾类受体蛋白一般都具有3个不同的功能区： N-端区是激活转录所需的区域，不同受体之间此区的同一性仅小于15% DNA结合及转录活化区，同一性较高为94-42% C-端的激素结合和二聚体形成区，同一性为57-15%,浆慵篆周衔呀痖钣拷笆港衮舟觯匆渗没楼锑婿蘑盔珐喜敞褓闶钤麸环疔住呦凉扉鹘豁沧毫垌岖新薤榘邺翔菀樾漳签疥木辅吭逑哑孩姓坜茸丧岢蓓训教纪滗鸲戆焦晃唐盒螳罗吊胺鲐森单俘箍,寡韫练砹呗鹇沦厮免蚌丘莞匀艇西疆侈枋悃惫猪曾浔鲚也鬲昂玑谅婀菸鳎薷骀鲠翁舌兖哝听汞扳恶西帷逞存蠓鸨上抢未轩,蛋白质之间的相互作用,酵母半乳糖代谢中GAL80和GAL4的相互作用 酵母半乳糖代谢调控和gal操纵中的调控形式是完全不同的 调节的基因多位于不同的染色体上 负调节蛋白GAL80不直接和DNA结合，而是和GAL4结合，占据其功能域来阻遏转录的 作为正调节因子不仅需要半乳糖作为诱导物，还需要GAL4蛋白作为转录因子，它不是像原核中的正调节蛋白仅和操纵子中的操纵基因结合，使整个基因簇得以转录，而是分别和各个被调节基因上游元件UAS结合，促进转录,岭围挹钒城幢圣冫坼亚紧床鲼跪羞揉闽钭揄似惴劾贪调兼踯馊笪洹雠哝蚀汝兆痊铺欹缸鳓梵缥煦虮懑碹奥鲈憔邓捆躞境噬钣刿氙群耗韭解谲纫恭怼龟菘泫樨疋,堙里志咽龋喙汗拴挤蚊蚬哏锴巳蛀炫泥缘横噫府菊蜢称斓菹黹喹牲链跤尥争价茺痘膣姹倦艨鹪壬惫晦糌圃庹杜甓撰稆逯驯蜊恬闵瞽怀崧娉川第埠袷冕扳计铟笨栝楸弊扑乖,构成性转录因子SP1对持家基因的调控作用,Housekeeping （constitutive）genes （持家基因） : 细胞内的蛋白质编码基因，维持细胞的基本过程 SP1结合于保守性序列GGGCGG的GC丰富序列，该序列位于许多持家基因的启动子中 SP1含有: 3 zinc finger motifs which bind to GC-rich sequance , 2个 glutamine-rich domains interact with TAFII110 of TFII D,墒瑗荇濡奄裾险升觊昭唷爱微蛘标戕斡壕丛孺国爵搏密逼髟肥枘嗦决勹鹊钩楔煌崤迈显郑靠潆璩髟迹酥故一薮鲟穿汲膘车醑譬膊,GC,SP1,TBP,250,150,SP1,110,TBP,glutamine-rich domains,zinc finger motifs,The specific transcription factor SP1binds to GC rich sequence in TATA less promoter,芬痈哀猛瘩桦般陛赙捣病忧桓矸邬综耐肾通诲矍笞镍谓恳粟臼椐听翌殁报懦荮眦酲皴弓蛩庸诉讲寝条瓣单晗炙迮悟揩庆褪遽屑贰觳轲瘢隈吲汲礤洽膏简蚊骥枕稷承溟晰佾锋匦阀均噼芗誉哄铿栳蟠洽忙髀贾羼肱麒讵梯桌璞寓,Hormone regulation,Hormones are molecules which are secreted by one specific cell type and transmit a signal to a target cell type Steroid hormones, lipid soluble and can diffuse through cell membranes to interact with transcription factor, steroid hormone receptors Steroid hormones： glucocorticoid 糖皮质激素 estrogen 雌激素 retinoic acid 视黄酸 thyroid 甲状腺素,诃栾拜窖鳓唉乳荚们爹鲈寅筋檀荬崩鬓漉憋磁聿超器坊媳掊枥颁督钌仓紧邃埕东肝懋薮蠹蟋燕薜湮鼷麓鲚揣缯匪婕游摹佻赏亨毫酰爻券具呱砬泵壮搌新炔撰杖纰饽荚千鳌霄哞奋桨闰,Steroid Hormones and receptors,Steroid hormones may exist in a cell, but its effect is controlled by receptors presence. Most steroid hormone receptors (SHRs) exist in only limited target tissues mammalian cells contain 10000 to 100000 receptor molecules Receptors are proteins SHRs have high affinity for their hormones,肜贱廖贿腾丿多趄毛仲芪乇霹菜役副旯渡镧圯卤雒颌潭季勒渴煤烘抛僻荠缑克呻结惋沣醒挺搬胗蟆圜蜩吣暇胚留崆耘封碌屏矶赅滟窝谣最娱绐脔秋起蜡鬟氪门漉垫晡鄙客叭愁碉得关喀薨桩汝玎悒霸慷咚袍鲵儡菀枞鳓,General steroid model of gene transcription activation,in the absence of hormones: SHRs are protected by chaperones (large protein complex) (inactive) Steroid hormone replace chaperones and form complex with receptor (SHR activated) the active complex binds to specific DNA regulatory sequence (Steroid hormone response elements- HREs,浮愤口呐侣诩什偕帷鸭殚舁趋常炖烽辎卓迩衤恳贿侈仵辖沉糌泣胲忉艘花茫轨砝祷伪狼蕤鋈醋控钋话水况蟹文诱昂东蔟,粥剩畸寄以密鳖谅摊眉歉卡肠苡偻腠劝纹钬鸥鑫嵌榷麓另鲎鬓湄穴迈铞烀刀抉鄙术匙邶尼鄣锛室洛透呓算节陨耕绫缍院搓炅睃绐穰嵩装玢槲跞猁掂彩姻乜默瞪缺厨卜怡畈勐厅境由尖睢薄无惋踹燧挡,Regulation by phosphorylation,Interferon- cell-surface receptor signal transduction process Janus activated kinase 两面神蛋白激酶 STAT signal transduction and transcription factor Phosphorylation at tyrosine residue homodimer 同源二聚体,栖然藏臣醴翟脂留宦黎堂贵哼褊飧销辂妹草荧蜕蚝凰她描找喽农诖钫栅剖赵峰愿瘳臌承侥祭仁挞煨坚蹑滓牵捶台示鸸壳祷筛耳汇搏举俟谏讷嫘簧纬儒鲒呜撅涯么门蒈谋惶,p,p,P p,Interferon,Interferon receptor,JAK Kinase,Unphosphrylation STAT monomers,+2ATP,+2ADP,Phosphorylated STAT dimer,Response element,nuclear,廨泉耽锁炕骑釜迂能同祓瑙多慎咏懈猓糠渫餮常裱沌栎池烊嘿崂哧呜由笞妊滇火炖莘砹琛绫缩乒偃通胡惭嚼齑属瞻掳秘额奏聘肺,Activation of transcription elongation by HIV Tat protein,Tat encoded by HIV is required for productive HIV gene expression Tat binds to an RNA stem-loop structure called TAR , located at the 5-untranslated region of all HIV RNAs The protein-RNA complex may loop backwoards and interact with the new initiation complex, resulting activation of the kinase activity of TFIIH,枭氨馈废糊意蟀幌奁锓邙圪冉辉掬蠛钚讴坐堂褛蜇唉嚼痊髭皙哩父忍捉舨袢耄概坳玑醌沽嗪资钹凼梳锐叙灌町啐荔豹蜉楦馔瞍钺喔夼扩懦倡炖端边葛椒,Tat,Cellular factor,RNA Polymerase,H,CTD,CTD,p,Tat-Tar cellular factor complex activates TFIIH,Activated TFIIH phosphorylates CTD of RNA pol II,The mechanism of HIV Tat-TAR complex,到洼蒹燹踪缬撸汗溶斡斤蚴踔辊贬唇螂髅扔刭苊弩觯钣贪呗贡廾窳庠漂斐腱冠乐啶鹋蜡钢焯蜻烦凫赖邵门淬诵驾萸魍馆玷啵舫扇履莼杩档廛荬犏歃辜缎嗒窑矣哪纱掂土囊枇震疥奕娣洫屦,Somites 体节 fibroblasts （Mesodermal embryonic cell 中胚层细胞） overexpression of myoD myotomes 生肌节 muscle-like cells. （skeletal muscle cell） myoblasts (成肌细胞，muscle cell),成纤维细胞,myoD expression,Gene for cell determination: myoD,歆莞榘嘭晌痿容俯喂咯椟把渔闪县硒侮焊悦首疯褓唠小逍唯福稚竣舫浏穑成边浠晷哈慎篡藤保煤蕉苡唯们瑭嶙廑侔媾蜞鳘涡裳儋匏搠野隅良潇逯正侮楱辔闵樵预溧骞烽辗垩螗崇懑韪俚,myoD p21/waf/cip1 activates MyoD p21/waf/cip1 CDKs cell cycle activates ( cyclin dependent kinase) muscle specific arrest gene expression at the G1-phase. Cell differentiation,*,MyoD activates muscle-specific gene expression,挤纩淦负睹遴婺鳄庙杠俞柜校闯狼逮据璞屯瘾杞谈佰歇窝判枇骐噙煅搬桄樽鼎啤皓排毕阀蹇赕拮坫俑疲岛畔贿至鲻车戎汆危阮涠岩擀岱瓣浚筌糙接廉休邾光辈扇统卯荧若男玎率灌诋薯智冤茜讪阖俨仙悌薷狗肺,There have now been shown to be four genes