姜生秀，李德祿

(甘肅省治沙研究所，民勤沙生植物園，甘肅民勤 733300)

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植物絲裂原活化蛋白激酶級(jí)聯(lián)信號(hào)轉(zhuǎn)導(dǎo)通路研究進(jìn)展

姜生秀，李德祿*

(甘肅省治沙研究所，民勤沙生植物園，甘肅民勤 733300)

摘要:絲裂原活化蛋白激酶(MAPK)是酵母、動(dòng)物和植物等真核生物中普遍存在和高度保守的一類(lèi)信號(hào)轉(zhuǎn)導(dǎo)通路，由MAPKKK、MAPKK和MAPK等3部分組成，在應(yīng)對(duì)生物非生物脅迫、激素、細(xì)胞分裂調(diào)控及植物生長(zhǎng)發(fā)育等過(guò)程中發(fā)揮重要作用。該文對(duì)近年來(lái)國(guó)內(nèi)外有關(guān)MAPK級(jí)聯(lián)通路的組成、在植株體內(nèi)的生物學(xué)功能以及MAPK通路的失活進(jìn)行了概述，旨在為今后MAPK通路介導(dǎo)的信號(hào)轉(zhuǎn)導(dǎo)機(jī)制的研究提供參考依據(jù)。

關(guān)鍵詞:絲裂原活化蛋白激酶(MAPK)；信號(hào)轉(zhuǎn)導(dǎo)；生物學(xué)功能

各種外界和內(nèi)部信號(hào)分子調(diào)節(jié)著植物的生長(zhǎng)和發(fā)育，細(xì)胞內(nèi)的受體蛋白通過(guò)識(shí)別胞外信號(hào)分子并將其向下游傳遞，從而引起一系列的生物化學(xué)反應(yīng)及蛋白之間的相互作用，這個(gè)過(guò)程被叫做細(xì)胞信號(hào)轉(zhuǎn)導(dǎo)[1]。信號(hào)轉(zhuǎn)導(dǎo)是真核細(xì)胞應(yīng)對(duì)外界信號(hào)及調(diào)節(jié)復(fù)雜胞內(nèi)變化的一種重要途徑，在調(diào)控細(xì)胞增殖、新陳代謝、變異和生存等細(xì)胞過(guò)程中發(fā)揮重要作用[2]。

外界環(huán)境脅迫下，植物信號(hào)轉(zhuǎn)導(dǎo)通路可分為四大主要類(lèi)型：絲裂原活化蛋白激酶級(jí)聯(lián)途徑、Ca2+依賴(lài)信號(hào)轉(zhuǎn)導(dǎo)通路、Ca2+依賴(lài)的鹽過(guò)敏感(SOS)信號(hào)通路和ABA信號(hào)轉(zhuǎn)導(dǎo)通路[3]。其中，絲裂原活化蛋白激酶(MAPK)級(jí)聯(lián)途徑是酵母、動(dòng)物和植物等真核生物中普遍存在和高度保守的一類(lèi)信號(hào)轉(zhuǎn)導(dǎo)通路[4]。MAPK級(jí)聯(lián)途徑包括三個(gè)功能性串聯(lián)的蛋白激酶：絲裂原活化蛋白激酶激酶激酶(MAPKKK)、絲裂原活化蛋白激酶激酶(MAPKK)和絲裂原活化蛋白激酶(MAPK)[5]。不同的MAPK通路感應(yīng)不同的外界信號(hào)刺激?，F(xiàn)已證明，在植物中，MAPK通路在應(yīng)對(duì)生物非生物脅迫、激素、細(xì)胞分裂調(diào)控及植物生長(zhǎng)發(fā)育等過(guò)程中發(fā)揮著重要作用[4]。

1MAPK級(jí)聯(lián)通路的組成

MAPK級(jí)聯(lián)途徑由MAPKKK-MAPKK-MAPK三級(jí)激酶系統(tǒng)組成，MAPKK被上游的MAPKKK磷酸化，磷酸化位點(diǎn)為Ser/Thr殘基，該位點(diǎn)氨基酸序列為SXXXS/T(X代表任何氨基酸)，反過(guò)來(lái)，MAPKK磷酸化MAPK，磷酸化位為T(mén)hr或Thr殘基，由此使信號(hào)逐級(jí)放大并傳遞到下游[5]。

1.1絲裂原活化蛋白激酶激酶激酶(MAPKKK)

MAPKKK是級(jí)聯(lián)反應(yīng)的第一部分，被認(rèn)為是目前MAPK級(jí)聯(lián)途徑中最復(fù)雜和數(shù)量最多的部分。擬南芥(Arabidopsisthaliana)中已被確認(rèn)有80多種，被分為3個(gè)亞族：MEKKs亞族，有21個(gè)；Rafs亞族，有48個(gè)；ZIKs亞族，有11個(gè)成員[6]。在Rafs亞族中，各蛋白激酶的結(jié)構(gòu)域十分保守，其中功能缺失突變基因CTRl(Constitutive triple response 1)在乙烯介導(dǎo)的信號(hào)轉(zhuǎn)導(dǎo)途徑中組成性表達(dá)，編碼負(fù)調(diào)節(jié)子，抑制乙烯誘導(dǎo)基因的表達(dá)[7]，Raf型CTR1基因EDR1在植物防御響應(yīng)中起到負(fù)調(diào)節(jié)作用[8]，At1g73660是一種Raf型MAPKKK成員，可以減弱擬南芥的耐鹽性[9]。MAP3K中的MEEK可以被磷酸化激活(即為MAP4K)，也可以被Ras或Rho家族的小GTP結(jié)合蛋白結(jié)合而產(chǎn)生活性[10]。MEKKK型ANP1基因具有應(yīng)對(duì)氧化脅迫、誘導(dǎo)特異脅迫應(yīng)答基因的表達(dá)及阻止植物激素的功能[11]，如煙草(Nicotianatabacum)MEKKK型基因NPK1能增強(qiáng)轉(zhuǎn)基因植物對(duì)非生物脅迫的耐受性[12]。AtMEKK1和AtMEKK4可受到滲透、機(jī)械損傷和病原的誘導(dǎo)[6]，AtMEKKs亞組中的ANPKls與調(diào)控H2O2的信號(hào)傳導(dǎo)有關(guān)[13]。NPKl蛋白激酶大量存在于側(cè)根原基和根莖頂端分生組織之間，與植物細(xì)胞的分裂和增殖有關(guān)[14]。ZIKs亞族中的蛋白激酶主要與MAPKs途徑的調(diào)節(jié)子ZRl的表達(dá)作用有關(guān)[15]。

1.2絲裂原活化蛋白激酶激酶(MAPKK)

植物MAPKK在MAPK級(jí)聯(lián)途徑中的成員數(shù)量最小，到目前為止，擬南芥基因組中已報(bào)道了至少60個(gè)MAPKKK和20個(gè)MAPK，但只有10個(gè)MAPKK被發(fā)現(xiàn)。上游的MAPKKK感應(yīng)外界信號(hào)，通過(guò)10個(gè)MAPKK傳遞到20個(gè)MAPK中，表明MAPKK是上游逆境信號(hào)的聚集點(diǎn)，也是下游MAPK的分枝點(diǎn)[5]。MAPKK是雙重特異性激酶，植物MAPKK最少的信號(hào)序列是S-T-XX-G-T-X-X-Y-M-X-P-E-R，植物MAPKK有保守的S/T-X5-S/T序列，而動(dòng)物激酶的序列為S/T-X3-S/T；根據(jù)氨基酸序列比對(duì)將擬南芥的MAPKK分為4個(gè)組，分別為A、B、C和D，其中C組和D組的MAPKK的編碼基因不含內(nèi)含子。植物MAPKK 的N端延伸表明了有一個(gè)假定的MAPK切入點(diǎn)，序列為[K/R][K/R][K/R]x(1-5)[L/I]x[L/I] ，類(lèi)似在動(dòng)物MAPKK中發(fā)現(xiàn)的序列[15]。另外，MAPKK有很高的底物特異性。

1.3絲裂原活化蛋白激酶(MAPK)

MAPK是級(jí)聯(lián)反應(yīng)的最后一部分，在連接上游組分和下游底物中起到重要作用[16]，MAPK能磷酸化特異效應(yīng)蛋白，從而激活細(xì)胞的響應(yīng)元件。自從苜蓿(MedicagosativaLinn.)中首次發(fā)現(xiàn)MAPK以來(lái)，至今在植物中已有大量MAPK被發(fā)現(xiàn)，基因組測(cè)序技術(shù)顯示在擬南芥中有20個(gè) MAPK[17]，水稻(Oryzasativa)有17個(gè)[18]，楊樹(shù)(Populus)有21個(gè)[19]。根據(jù)編碼的蛋白序列的TXY基序的不同，可將其分為T(mén)EY類(lèi)和TDY類(lèi)，根據(jù)系統(tǒng)發(fā)生關(guān)系將TEY類(lèi)進(jìn)而劃分為A、B、C組，TDY類(lèi)單獨(dú)列為D組[20]。據(jù)報(bào)道，A類(lèi)有AtMPK3、AtMPK6和OsMAPK5；B類(lèi)有AtMPK4和ZmSIMK1；C類(lèi)有AtMPK1、AtMPK2、PsMPK2和GhMPK7。這些MAPK在植物脅迫響應(yīng)和生長(zhǎng)發(fā)育過(guò)程中都發(fā)揮著重要作用[21]，如擬南芥的AtMPK3可被多種環(huán)境脅迫激活，氧化脅迫也能激活該激酶[22]；應(yīng)用MPK4的特異性抗體分析顯示AtMPK4參加生物和非生物脅迫應(yīng)答[23]；PsMPK2在擬南芥中過(guò)表達(dá)其活性受機(jī)械傷害以及其他脅迫信號(hào)諸如ABA、H2O2等誘導(dǎo)[24]。從單子葉植物中獲得了詳細(xì)的D類(lèi)MAPK功能資料，如OsBWMK1誘導(dǎo)PR基因的表達(dá)，并增強(qiáng)了植物抵抗真菌和細(xì)菌感染的能力[25]；AtMPK9優(yōu)先在保衛(wèi)細(xì)胞中表達(dá)，具有功能冗余性，在ABA信號(hào)通路中對(duì)活性氧下游起到正調(diào)控的作用[26]；AtMPK18有能調(diào)節(jié)植物細(xì)胞皮層微管的功能[27]；棉花(Gossypiumspp.)GhMPK16的表達(dá)受化學(xué)和生物信號(hào)的誘導(dǎo)[28]。

2MAPK級(jí)聯(lián)反應(yīng)的功能

植物在整個(gè)生命周期中經(jīng)常受到各種生物和非生物脅迫，干旱、鹽和低溫等是造成植物減產(chǎn)的主要因素，為應(yīng)對(duì)它們生存的限定因素，植物具有感知和傳遞刺激信號(hào)的能力，其中，MAPK級(jí)聯(lián)通路將感知到的刺激信號(hào)傳遞到細(xì)胞中，然后生物體通過(guò)蛋白質(zhì)的磷酸化和去磷酸化實(shí)現(xiàn)對(duì)逆境的調(diào)控[29]。

2.1MAPK參與的植物化學(xué)信號(hào)途徑

目前已有很多證據(jù)證明MAPK途徑參與了植物化學(xué)信號(hào)途徑，研究較多的植物內(nèi)源信號(hào)分子中，有水楊酸(SA)、茉莉酸(JA)和吲哚乙酸(IAA)等。OsBIMK1基因的表達(dá)受化學(xué)分子如JA、BTH的誘導(dǎo)[30]；OsMSRMK2表達(dá)受JA誘導(dǎo)[31]；OsSIPK穩(wěn)定期的mRNA分析表明該基因在2周大的水稻幼苗中微弱組成型表達(dá)，當(dāng)用環(huán)己酰亞胺(CHX)、JA和SA處理時(shí)，OsSIPK的轉(zhuǎn)錄水平會(huì)增強(qiáng)[32]；AtMPK4在SA通路中起到負(fù)調(diào)控作用，而在JA通路中起到正調(diào)控作用[33]。SA含量的積累不僅造成細(xì)胞的死亡，也會(huì)激活MAPK信號(hào)通路。如Liu等[34]發(fā)現(xiàn)大豆(Glycinemax)中GmMPK4s的沉默導(dǎo)致葉片細(xì)胞的死亡和SA含量的升高。

2.2MAPK參與植物生物脅迫下的信號(hào)傳導(dǎo)

自然界各種病原體威脅著植物的生長(zhǎng)，植物自身形成了多種防御措施，除了化學(xué)和物理障礙措施外，還通過(guò)病原體誘導(dǎo)措施來(lái)保護(hù)自己，包括細(xì)胞壁增厚、產(chǎn)生植物抗毒素、激活防御基因活性等[35]。Suzuki等[36]用從疫霉菌(Phytophthorainfestans)衍生而來(lái)的一種誘導(dǎo)子處理煙草懸浮細(xì)胞時(shí)發(fā)現(xiàn)，47 kDa的 MAPK快速而短暫地被激活。Zhang等[37]發(fā)現(xiàn)當(dāng)煙草感染花葉病毒時(shí)，煙草中有2種MAPK被激活，分別是 48 kD的水楊酸(SA)誘導(dǎo)蛋白激酶(SIPK)和44 kD的創(chuàng)傷誘導(dǎo)蛋白激酶(WIPK)。He等[38]從水稻中克隆獲得了一種MAPK基因BWMK1，該基因在水稻感染稻瘟菌4 h后表達(dá)。據(jù)最近的報(bào)道，AhMPK3在轉(zhuǎn)基因煙草中過(guò)表達(dá)增強(qiáng)了煙草對(duì)斜紋夜蛾(Spodopteralitura)的耐受性[39]，GhMPK16在擬南芥中的異位表達(dá)增強(qiáng)了植物的抗病性[38]。Northern雜交顯示，GhMPK7的轉(zhuǎn)錄水平受病原體誘導(dǎo)，轉(zhuǎn)化煙草后，轉(zhuǎn)基因煙草表現(xiàn)出了很強(qiáng)的抵抗煙草炭疽病菌(Colletotrichumnicotiana)和病毒PVY的能力，并且SA通路基因的轉(zhuǎn)錄水平也得到了快速的增強(qiáng)[40]?？梢?jiàn)，MAPK參與植物生物脅迫下的信號(hào)傳導(dǎo)。

2.3MAPK途徑在植物激素信號(hào)轉(zhuǎn)導(dǎo)通路中的作用

脫落酸(ABA)在種子萌發(fā)、氣孔調(diào)節(jié)和干旱、鹽、低溫等非生物脅迫中都起到一定的作用，ABA對(duì)逆境脅迫的適應(yīng)作用主要是通過(guò)誘導(dǎo)必要的脅迫相關(guān)基因的表達(dá)來(lái)實(shí)現(xiàn)。在糊粉層細(xì)胞中，ABA快速而短暫地激活MAPK的活性，而赤霉素(GA)則抑制MAPK的轉(zhuǎn)錄水平。PsMAPK3在豌豆(Pisumsativum)中的表達(dá)受GA、6-BA誘導(dǎo)[41]，而轉(zhuǎn)PsMPK2基因擬南芥中PsMPK2和AtMPK1 及AtMPK2一樣具有ABA和H2O2耐受性[42]；擬南芥中ABA激活A(yù)tMPK3和p46MAPK的活性[43]，而水稻中OsMAPK5的活性受ABA的激活[44]；棉花GhMPK6基因參與ABA誘導(dǎo)的CAT1的表達(dá)[45]；ABA可以誘導(dǎo)玉米ZmMPK5少量表達(dá)[46]；GhMPK2在煙草中過(guò)表達(dá)致使植物降低對(duì)ABA的敏感性[47]。

乙烯是植物生命活動(dòng)中的重要調(diào)節(jié)物質(zhì)，參與植物的果實(shí)成熟和花葉衰老等過(guò)程，也有誘導(dǎo)防御體系的功能，例如，當(dāng)煙草受到病原體侵害時(shí)，其葉片就會(huì)快速誘導(dǎo)蛋白的磷酸化，從而對(duì)病原菌起抑制作用[48]。TR1、ETR2和EIN4是乙烯的受體，CTR1編碼一種和Raf家族相似的蛋白；CTR1在乙烯信號(hào)通路中作為負(fù)調(diào)控因子，它在乙烯受體的下游，乙烯受體結(jié)合并激活CTR1[49]。很多人認(rèn)為MAPK通路參與了乙烯信號(hào)轉(zhuǎn)導(dǎo)，如用乙烯處理煙草葉片后會(huì)激活一種50 kD大的 MBP激酶，這種激酶是CTR1下游的一種MAPK激酶[50]。

植物生長(zhǎng)素在植物生長(zhǎng)和發(fā)育過(guò)程中也起到很重要的調(diào)節(jié)作用，如頂端優(yōu)勢(shì)、側(cè)根和根須的形成及微管的變異等。很多研究發(fā)現(xiàn)了蛋白激酶和磷酸酶在生長(zhǎng)素信號(hào)通路中的作用，首先證明了MAPK是參與生長(zhǎng)素信號(hào)轉(zhuǎn)導(dǎo)的一種激酶，將缺少生長(zhǎng)素的煙草BY-2細(xì)胞用合成生長(zhǎng)素，即2,4-二氯苯乙酸 (2,4-D)進(jìn)行處理，結(jié)果46 kD的 MBP激酶被快速激活[51]；此外，用生長(zhǎng)素處理后，一種磷酸化重組AtMPK2蛋白激酶的活性也得到了增強(qiáng)。這些結(jié)果表明MAPKK和 MAPK在生長(zhǎng)素介導(dǎo)的信號(hào)轉(zhuǎn)導(dǎo)中發(fā)揮著一定的作用[52]。

2.4MAPK與非生物脅迫信號(hào)的關(guān)系

植物在生存的過(guò)程中要應(yīng)對(duì)各種非生物脅迫，包括干旱、高溫低溫和滲透脅迫等。例如，在擬南芥中，冷和鹽脅迫能誘導(dǎo)完整的MAPK級(jí)聯(lián)途徑：MEKK1-MKK2-MPK4[53]，MAPKK4和MAPKK6被冷和鹽誘導(dǎo)，而MAPKK1被鹽和干旱誘導(dǎo)，MAPKK10-2只被冷脅迫誘導(dǎo)[54]；煙草的一個(gè)MAPKK家族SIPKK，當(dāng)植物受到創(chuàng)傷之后其表達(dá)量升高[55]；大豆GMK1的活性在鹽脅迫下被激活[56]；黃瓜(CucumissativusLinn.)CsNMAPK在轉(zhuǎn)基因煙草中受到鹽脅迫和滲透脅迫誘導(dǎo)[57]；蘋(píng)果砧木山定子(MalushupehensisRehd. var.pinyiensisJiang)的葉和根中MhMAPK的mRNA水平被干旱和鹽所誘導(dǎo)[58]；在鹽和滲透脅迫下，TMKP1在小麥(TriticumaestivumLinn.)中被誘導(dǎo)表達(dá)[59]；海蓬子 (Salicorniabrachiata)SbMAPKK的轉(zhuǎn)錄水平被旱、冷和鹽誘導(dǎo)，并在鹽誘導(dǎo)下的轉(zhuǎn)錄水平最高[60]。ZmSIMK1在擬南芥中的過(guò)表達(dá)增強(qiáng)了植物的耐鹽性，并且誘導(dǎo)了脅迫相關(guān)基因RD29和P5CS1的表達(dá)[61]。水稻中OsMAPK44的活性受鹽、干旱和氧化脅迫誘導(dǎo)，但不受冷脅迫誘導(dǎo)[62]，而OsMAPK33在干旱脅迫下其轉(zhuǎn)錄水平升高，而在鹽脅迫下轉(zhuǎn)錄水平下降[63]。棉花中，GhMPK2和GhMPK16具有耐受滲透脅迫的能力[64]，將GhMPK3轉(zhuǎn)化煙草中增強(qiáng)了轉(zhuǎn)基因煙草的耐旱性和耐氧化性[65]。

活性氧(ROS)是多種脅迫信號(hào)通路的中間信號(hào)分子，非生物脅迫導(dǎo)致ROS在植物體內(nèi)的積累，MAPK級(jí)聯(lián)通路不僅可以被ROS誘導(dǎo)，也可以調(diào)節(jié)ROS含量。在滲透脅迫下，煙草中過(guò)表達(dá)的ZmMPK7基因通過(guò)調(diào)節(jié)過(guò)氧化物酶(POD)活性降低ROS造成的傷害[66]。水稻中，MAPKKK的DSM1通過(guò)ROS的清除參與和干旱脅迫有關(guān)的信號(hào)通路[67]。當(dāng)植物受到創(chuàng)傷時(shí)，AtMPK8通過(guò)整合ROS、Ca2+和蛋白的磷酸化作用對(duì)ROS的體內(nèi)平衡起到調(diào)節(jié)作用[68]。

另外，已有證據(jù)表明低溫影響許多植物蛋白的磷酸化位點(diǎn)。Northern雜交結(jié)果表明，ZmMPK17的轉(zhuǎn)錄水平受多種逆境脅迫誘導(dǎo)，在煙草中的過(guò)表達(dá)增強(qiáng)了植物對(duì)低溫的耐受性[69]。Berberich 等[70]從玉米中分離出了ZmMPK4，轉(zhuǎn)入煙草中發(fā)現(xiàn)該基因增強(qiáng)了轉(zhuǎn)基因植株對(duì)低溫的耐受性。馬郁蘭(OriganumonitesL.)OoMAPKK1在低溫脅迫下表達(dá)量明顯升高[71]。在低溫條件下，OsMAPK2的mRNA積累量顯著升高[72]。

3MAPK通路的失活

MAPK級(jí)聯(lián)途徑的失活和活化同等重要，MAPK的失活是通過(guò)TXY 域里Ser或Tyr的去磷酸化來(lái)調(diào)節(jié)。目前，已克隆獲得了一些酵母和動(dòng)物的磷酸化酶，發(fā)現(xiàn)它們具有使MAPK失活的功能，這類(lèi)酶至少可以被分為3類(lèi)：雙特異性磷酸酶(DsPTPases)，能使MAPK在Ser或Tyr位點(diǎn)去磷酸化；酪氨酸磷酸化酶(PTPases)，只在Tyr位點(diǎn)去磷酸化；絲氨酸/蘇氨酸磷酸化酶(PPases)[52]。DsPTPases具有活性位點(diǎn)VXVHCXXGXSRSXTXXXAY(L/I)M，這個(gè)特異的域和PTPase有同源性，因此，又可把PTPase和DsPTPases歸為同一類(lèi)[73]。

迄今，有很多研究證明了高等植物中MAPK 的激活伴隨蛋白激酶中Tyr的磷酸化，這些研究為MAPK自磷酸化或Tyr位點(diǎn)被磷酸化提供了證據(jù)，同時(shí)也證明了植物具有酪氨酸磷酸化酶，在Tyr位點(diǎn)去磷酸化并且使MAPK失活[74]。擬南芥雙特異性磷酸酶AtDsPTP1在Tyr位點(diǎn)去磷酸化，并使AtMPK4失活，導(dǎo)致AtDsPTP1在不同的脅迫下于不同組織中組成型表達(dá)[73]。另外，編碼PTPase的一些基因的表達(dá)并不受MAPK通路的調(diào)節(jié)[75]。擬南芥AtPTP1的轉(zhuǎn)錄水平受到高鹽脅迫誘導(dǎo)和低溫的抑制，AtPTP1具有去磷酸化功能，在體外能使一種MAPK失活[76]。Gupta等[77]在研究MAPK活性的實(shí)驗(yàn)中發(fā)現(xiàn)，AtMPK6的活性受H2O2調(diào)節(jié)， 在體外AtPTP1 能使AtMPK6失活；最近從豌豆和大豆中也分離得到AtPTP1[78]。Haring等[79]從衣藻屬(Chlamydomonas)中分離出了一種雙特異性磷酸酶VH-PTP13，具有去磷酸化的功能，因此在體外能使紫花苜蓿中的SIMK和MMK2失活。

4展望

MAPK級(jí)聯(lián)途徑作為細(xì)胞信號(hào)轉(zhuǎn)導(dǎo)途徑中重要的組成部分，已有越來(lái)越多的MAPK基因從植物中克隆獲得，并對(duì)其功能開(kāi)展了研究。目前，對(duì)于MAPK基因功能和作用原理的研究只是現(xiàn)象描述，還存在很多問(wèn)題，因此，對(duì)MAPK級(jí)聯(lián)途徑的諸多方面還有待進(jìn)一步探討。主要包括以下幾個(gè)方面：(1)植物在進(jìn)化過(guò)程中形成了一套非常完善的感應(yīng)外界刺激的機(jī)制，各種各樣的蛋白激酶及同一類(lèi)激酶的不同亞類(lèi)之間在信號(hào)傳遞過(guò)程中有交叉作用，所以在現(xiàn)有研究基礎(chǔ)上需要進(jìn)一步弄清各種蛋白激酶之間的相互關(guān)系；(2)進(jìn)一步闡明MAPK級(jí)聯(lián)途徑的下游事件及在植株體內(nèi)介導(dǎo)的生化代謝和生理調(diào)控過(guò)程；(3)闡明植物中與MAPK級(jí)聯(lián)途徑相關(guān)的信號(hào)轉(zhuǎn)導(dǎo)分子途徑，以及MAPK級(jí)聯(lián)途徑與植物細(xì)胞中其他信號(hào)途徑的動(dòng)態(tài)互作關(guān)系。

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(編輯:裴阿衛(wèi))

文章編號(hào):1000-4025(2016)06-1278-07

doi:10.7606/j.issn.1000-4025.2016.06.1278

收稿日期:2015-12-29;修改稿收到日期:2016-05-19

基金項(xiàng)目:甘肅省自然基金 (1308RJYA091)；典型沙生植物生態(tài)適應(yīng)機(jī)制及其進(jìn)化策略研究(145RJIA335)

作者簡(jiǎn)介:姜生秀(1987-)，女，碩士，研究實(shí)習(xí)員，主要從事植物抗逆分子生物學(xué)研究。E-mail:yanyunjiang1987@163.com *通信作者:李得祿，副研究員，主要從事荒漠植物及荒漠化防止研究。 E-mail:lidlu2008@163.com

中圖分類(lèi)號(hào):Q257

文獻(xiàn)標(biāo)志碼:A

Research Progress of Mitogen-activated Protein Kinase Signal Transduction Pathway

JIANG Shengxiu, LI Delu*

(Gansu Psammophyte Engineering Technology Research Center, Minqin Desert Botanical Garden, Minqin， Gansu 733300，China)

Abstract:Mitogen-activated protein kinase(MAPK) cascades are highly conserved signaling modules found in all eukaryotes, including fungi, plants and animals.A MAPK cascade generally consists of three components:a MAPKKK (MAPKK kinase), a MAPKK (MAPK kinase) and a MAPK, and they play essential roles in abiotic stresses, hormones, cell division and plant growth and development.In this article,we outlined the compositions,biological functions, inactivation of MAPK cascades,which aimed at providing some references basis for the research of MAPK- mediated signal transduction mechanisms.

Key words:Mitogen-activated protein kinase(MAPK); signal transduction pathway; biological functions