孫淑豪 余迪求
(中國科學院西雙版納熱帶植物園 熱帶植物資源可持續(xù)利用重點實驗室,昆明 650223)
WRKY轉錄因子家族調控植物逆境脅迫響應
孫淑豪 余迪求
(中國科學院西雙版納熱帶植物園 熱帶植物資源可持續(xù)利用重點實驗室,昆明 650223)
WRKY轉錄因子是一組含有保守的WRKYGQK結構域的蛋白質家族,廣泛參與植物的營養(yǎng)體生長、器官發(fā)育、物質代謝和對各種生物、非生物脅迫的響應過程。目前,對WRKY家族轉錄因子的研究主要集中在不同物種中WRKYs對逆境脅迫響應的信號轉導機制的解釋。以近年來發(fā)表的關于WRKYs的研究成果為基礎,綜述了WRKY家族成員的不同功能,討論了WRKYs的不同成員在植物正常生長發(fā)育的重要作用。模式植物之外其他的植物物種中WRKY家族成員的作用報道相對較少,且缺少全面的研究和分析;WRKYs參與的很多信號通路還沒有完全清晰,這些問題有待深入研究。
WRKYs;生物脅迫響應;非生物脅迫響應;植物激素
DOI:10.13560/j.cnki.biotech.bull.1985.2016.10.009
植物時刻暴露在各種環(huán)境條件下,惡劣的環(huán)境條件阻礙著植物的生理性生長過程,這些惡劣的環(huán)境條件被稱為非生物脅迫/生物逆境,包括干旱、土壤鹽濃度、重金屬、低溫、放射性物質和不同類型的氧化還原反應病蟲害等[1]。植物體通過分子、細胞、形態(tài)建成各個層次產生對環(huán)境的適應性響應[2],這些復雜的調控網絡操縱著細胞和植物個體對環(huán)境的響應、對氣候的適應性[3]。病原體的入侵引起植物內源信號分子,如植物激素水楊酸(salicylic acid,SA)和 茉莉酸(jasmonic acid,JA)以及他們的衍生物含量的迅速升高,這對下游防御基因的表達有著重要的調控作用[4]。其中SA觸發(fā)植物體對于活營養(yǎng)體寄生病原體的防御反應,JA則是參與對死營養(yǎng)體病原菌的抗性[5]。ABA(abscisic acid)和乙烯(ethylene)對JA調控起協(xié)同作用,但他們都拮抗SA。生長素(auxin)、赤霉素(gibberellins)和細胞分裂素(cytokinins)則是優(yōu)先促進植物的生長過程,抑制脅迫響應基因的表達;但是這個過程可以被SA和JA所抑制,以犧牲植物生長的代價來進行逆境防御和抵抗[4]。
在過去的20年中,人們對WRKY轉錄因子(TF)家族參與植物對生物和非生物逆境響應的調控有了很多研究和認識[6],其在高等植物中是最大的轉錄因子家族之一,并且存在于所有綠色植物基因組中[7],也被稱為非生物脅迫響應的“中心調控因子”[8]。關于WRKY家族轉錄因子參與SA、JA逆境脅迫響應信號轉導過程的報道逐年增多。WRKYs調節(jié)植物對多種非生物脅迫響應,例如鹽脅迫[9]、干旱脅迫[10]、冷脅迫[11]、傷口反應[12];且不僅僅局限于模式植物擬南芥,還包括很多其他的物種[13]。WRKY蛋白在產生生物脅迫的病原體防御[14,15]和昆蟲防御[16,17]中起重要作用。本文主要總結了近年來報道的WRKYs參與植物脅迫響應的作用,希望對WRKY家族在植物逆境響應中的角色,有一個全面的認識。
WRKY家族轉錄因子具有相同的結構特征,N端都有包含WRKYGQK七肽序列的WRKY結構域,C端則含有C2H2-或C2HC-類型的鋅指結構[15]。根據這些特點,WRKYs可以分成三個家族:第Ⅰ家族含兩個WRKY結構域和兩個C2H2鋅指結構,第Ⅱ家族含一個WRKY結構域和一個C2H2鋅指結構,第Ⅲ家族含一個WRKY結構域和一個C2HC鋅指結構。第Ⅱ家族又被分成a,b,c,d 和e五個小亞族。第Ⅱ家族的WRKY蛋白參與調控植物的生長發(fā)育,例如衰老、種子休眠和萌發(fā)等;還參與植物對干旱、鹽脅迫和冷害響應過程[18]。 WRKYs如果沒有LZ(leucine zipper)基序,則不能形成同源或者異源二聚體[19]。
不同物種中WRKY家族基因數量也是不同的,黃瓜(Cucumis sativus)中57 個,麻風樹(Jatropha curcas)中58個,葡萄藤(Vitis vinifera)中9個,白梨(Pyrus bretschneideri)中103個,谷子(Setaria italica)中105個,蓖麻子(Ricinus communis L.)中58個,擬南芥(Arabidopsis thaliana)中74個,水稻(rice)中102個,楊樹(poplar)中104個,二穗短柄草(Brachypodium distachyon)中86個成員,182個成員在大豆中,116和102個WRKY基因在兩個不同的棉花種。 油菜(Brassica napus)中有287個WRKY家族基因,桑樹(Morus notabilis)中有54個WRKY家族基因,甜木薯(Manihot esculenta)中被鑒定出來85個WRKY家族基因[20-29]。
2.1WRKY轉錄因子響應生物逆境脅迫
AtWRKY50和AtWRKY51促進SA的生物合成[30]。AtWRKY17和AtWRKY33在JA處理過后被誘導表達[31]。過表達AtWRKY28和AtWRKY46經由SA信號通路可以誘導ICS1和PBS3[32]。此外,從長春花中分離到的12個WRKY基因都可以響應JA信號[33],丹參(Salvia miltiorrhiza)中的49個WRKY基因可以顯著被JA上調或者下調表達[34]。從楊樹(Populus trichocarpa)中分離的WRKY第III家族成員PtrWRKY89可以被SA快速誘導[35]。PtrWRKY89的過表達轉基因株系中檢測到PR基因持續(xù)表達,且該株系對P. syringae和B. cinerea更敏感。PtrWRKY89參與SA與JA的協(xié)同信號轉導過程[36]。在煙草中,WRKY 3/4基因可以被TMV、SA和SA類似物所快速誘導,且表達量足夠啟動PR蛋白合成,增強抵抗力[37]。我們的研究結果證實AtWRKY8通過直接調控ABI4、ACS6和ERF104的表達參與植物對TMV的防御響應過程中,并且介導了TMV和擬南芥之間ABA和乙烯的信號交叉?zhèn)鬟f[38]。香蕉VQ基因通過抑制冷害響應轉錄因子MaWRKY26參與到JA生物合成基因的調節(jié)[39]。人參中WRKY轉錄因子對于脅迫的響應有6個PgWRKY基因(PgWRKY2、PgWRKY3、PgWRKY4、PgWRKY5、PgWRKY6、PgWRKY7)參與。SA處理后3個WRKY基因(PgWRKY3、PgWRKY5、PgWRKY9)明顯表達量下調。ABA處理后5個PgWRKYs(PgWRKY2、PgWRKY4、PgWRKY5、PgWRKY8、PgWRKY9)一直明顯的上調表達[40]。
在水稻中,OsWRKY71[41]、OsWRKY31[42]、Os-WRKY45-1、OsWRKY45-2[43]都被報道在細菌病原菌侵染過程中被誘導。相似的,在擬南芥中,AtWRKY8[44]、AtWRKY33[45]、AtWRKY25[46]、AtWRKY11和AtWRKY17[31]在細菌病原體侵染時候基因下調表達。WRKY參與菜豆對于SCN大豆胞囊線蟲?。⊿oybean Cyst Nematode)的侵染脅迫響應[47]。CmWRKY15通過調控ABA信號途徑可以促進細極鏈格孢(Alternaria tenuissima)對于植物體的感染作用[48]。但是,CmWRKY48過表達的轉基因菊花卻可以抑制蚜蟲的群體數量[49]。
油菜在響應核盤菌侵染24 h內快速誘導的關鍵病原體響應基因,包括葡聚糖酶、幾丁質酶、過氧化物酶和WRKY轉錄因子等,這些都是參與宿主早期病原體響應的基因。其中,WRKY 11在24 hpi被誘導(3倍)但是在48 hpi被抑制(-2倍)[50];WRKY33之前被報道過正調控植物對于營養(yǎng)體壞死型真菌的抗性[51];而且在甘藍型油菜中過表達WRKY33導致抗性響應基因的持續(xù)表達,包括PR1、PDF1.2,增加了植株的抵抗力[52]。WRKY11、18、53則表現出了負調控或者是對病原菌侵染的延遲響應。在之前的報道中BnWRKY11在侵染早期6 hpi的時候,表達水平同時被JA和ET 所抑制[53]。
在擬南芥中過表達AtWRKY28和AtWRKY75都能增強植株對病菌的抗性反應[54]。實驗結果證明,13個 BnWRKYs都明顯地被S. sclerotiorum誘導;包括WRKY6、 8、11、15、28、33、 40、69 和75,在所有煙草株系中都能夠檢測到表達量的變化;其中6個被大幅上調,分別是BnaA08g12420D(WRKY11)、BnaC04g35770D(WRKY15)、BnaC06g-19560D(WRKY40)、BnaC06g40170D(WRKY40)、BnaA08g180-40D(WRKY65)和BnaA09g55250D(WRKY69),同時5個WRKYs被下調[55]。
WRKY40和銅離子轉運蛋白是調節(jié)棉花對于橘黃粉虱侵襲防御的中心調控基因[56]。OsWRKY53可以被咀嚼食草動物高粱條螟(SSB)啃食所誘導,負調控轉錄調節(jié)子OsMPK3/OsMPK6導致JA、JA-Ile和乙烯水平下降從而誘發(fā)水稻對SSB的抗性。褐飛虱(BPH)侵襲的8 h之內OsWRKY53轉錄水平上調,在水稻對于啃食性昆蟲BPH的抵抗起到重要作用。實驗發(fā)現,BPH可以導致水稻中H2O2的顯著減少,而在oe-wrky植物體中BPH誘導的H2O2含量明顯低于WT;說明OsWRKY53通過調節(jié)H2O2的水平來正調控水稻對啃食性昆蟲的防御方應[57]。
2.2WRKY轉錄因子調控非生物脅迫響應
干旱是所有非生物脅迫類型中對植物體傷害最大的,缺水使植株生長緩慢且矮小。WRKY家族轉錄因子在植物對干旱的耐受起到至關重要的作用[58]。CmWRKY10通過ABA途徑來調控菊花的干旱耐受性;在其高表達植株中DREB1A、DREB2A、CuZnSOD、NCED3A、 NCED3B等基因轉錄活躍,說明該株系的干旱耐受機制與ABA 信號途徑有關聯。另外,在高表達株系中ROS的積累明顯低于野生型,過氧化物酶、超氧歧化酶、過氧化氫酶的酶活性則是高于野生型,這些高酶活都對提高缺水耐受性有幫助[59]。CmWRKY1是從菊花重克隆出來的WRKYⅡb亞家族的轉錄因子,它和擬南芥AtWRKY6高度同源,外施ABA下調內源CmWRKY1,但是濕潤條件可以明顯的誘導CmWRKY1的表達[60]。CmWRKY1通過調節(jié)ABA相關基因表達增強杭菊的脫水耐受性。AtWRKY6調控有正調控和負調控兩種調控方式,而CmWRKY1經過證實同樣如此[61]。相反,過表達CmWRKY17則增加了菊花對于鹽脅迫的敏感性[62]。
AtWRKY46可以明顯地被干旱、H2O2、鹽脅迫等所誘導,它的突變體相比野生型來說對滲透脅迫更敏感[63]。TaWRKY44 在煙草中表達可以提高其對干旱、鹽脅迫、滲透脅迫的抗性[64]。研究結果顯示,OsWRKY11[65]、HvWRKY38[66]、TaWRKY2和TaWRKY19[67]都能提高植物對于干旱脅迫的抵抗能力。被HSP101調控的OsWRKY11可以增強水稻對高溫和干旱的耐受性[65]。相似的,在大豆中過表達GmWRKY54使得植物體對干旱的耐受性有明顯的提高[68]。WRKY基因還參與到大豆干旱和洪澇脅迫的響應過程中[69]。
從羊草(Leymus chinensis)中分離的LcWRKY5,在擬南芥中過表達LcWRKY5可以強烈地增強植物體的耐受性[70]。從短柄草(Brachypodium distachyon)中克隆到的BdWRKY36有增強干旱期間植株的適應性的功能。此外,過表達BdWRKY36蛋白的轉基因煙草對干旱的抵抗力顯著提高,這種增強作用是通過減少活性氧ROS的積累,激活抗性相關基因NtLEA5、ABA生物合成相關基因NtNCED1和調節(jié)基因NtDREB3等途徑來實現的[71]。與AtWRKY60同源的BhWRKR1,可以被缺水和ABA短暫而快速的誘導表達。BhWRKY1與BhGolS1互作,依賴ABA途徑來增加轉基因煙草對于水分缺失的耐受性[72]。大豆遭受水分脅迫時,GmWRKY17和GmWRKY67的轉錄激活作用增強。GmWRKY161在葉片中可被快速短暫誘導表達,在誘導3 h后達到峰值71倍。GmWRKY112在葉片中短暫上調,在處理2 h后達到最大值21倍。GmWRKY17和GmWRKY67轉入大豆根系中,干旱處理后分別有12.7倍和4.8倍的表達量。之前的研究已經表明GmWRKY53和GmWRKY112啟動子正響應外施用鹽和PEG[73]。煙草的轉錄因子NtWRKY69能夠直接被水分脅迫所誘導[74]。WRKY70還參與落花生的低溫脅迫響應[75]。互花米草珧冷脅迫響應中,WRKY起始了PR蛋白和AFP蛋白(anti-freezing protein)的表達[76]。WRKY44在煙草對多種非生物脅迫的耐受性起到重要作用[77]。
最近的一個研究顯示,來自于棉花(G. hirsutum L.)的GhWRKY68,在煙草中過表達該蛋白,可以通過ABA信號途徑來提高轉基因植物體對干旱和鹽脅迫的敏感性[78]。人參用NaCl處理時除了PgWRKY5之外所有的PgWRKYs轉錄水平都明顯的上調或者下調表達[79]。遏藍菜(Thlaspi caerulescens)的WRKY53[80]和擬南芥中AtMYB4[81]有可能參與到植物對于重金屬鎘(Cd)的脅迫響應過程中。怪柳(Tamarix hispida)的ThWRKY7可以特異性的結合到ThVHAc1啟動子的W-box上并且具有轉錄激活活性,而且在Cd處理條件下ThWRKY7與ThVHAc1具有相同的表達模式,表明ThWRKY7能夠提高植物對Cd的耐受性[82]。低氧濃度誘導屬于AUX/IAA、WRKY、HB、鋅指家族的轉錄因子的高表達,屬于WRKYs第Ⅰ家族的WRKY23和WRKY33在0.4 kPa時被誘導[83],他們可能與VQ蛋白協(xié)同作用[84]。在馬櫻丹(V. lantana)中WRKY蛋白對于O3脅迫在轉錄水平的響應,誘導一個參與O3脅迫感受/信號轉導途徑的基因表達并且參與氧化還原反應[85]。WRKY基因可能參與兩個楊樹雜交克隆受到O3間斷式脅迫條件下的氧化還原反應調控[86]。同樣的在Col-0擬南芥WRKY轉錄因子可以被O3(350 ppb,2 h)處理高度誘導,該現象也能在番茄被B. cinerea侵染和被P. syringae感染[87]、O3處理過后觀察到[88]。WRKY蛋白還參與毛竹(Phyllostachys edulis)對強光照的響應調控中[89]。
WRKY蛋白已經被證明參與植物的生長發(fā)育過程的調節(jié),例如毛狀體形態(tài)發(fā)生[90],開花[91],種子發(fā)育[92]、休眠和萌發(fā)[93],衰老[94]。擬南芥WRKY13通過直接結合于NST2的啟動子上正調控莖中木質素的生物合成[95]。在木髓部細胞中AtWRKY12直接抑制NST2的表達來負調控次級細胞壁(SCW)的形成,次級細胞壁相關的NAC結構域蛋白SND1/NST3和它的功能同源基因NST1和 NST2、維管特異性VND6和VND7是一個關鍵的調控節(jié)點,對于下游SCW生物合成基因SND3、MYB46、MYB83、MYB103等次級轉錄因子的轉錄具有開關作用[96,97]。PtrWRKY19與AtWRKY12具有高度同源性,都負調控木質部髓細胞的SCW發(fā)育[98]。WRKY還參與苜蓿(Medicago truncatula)的次級細胞壁形成以及表皮轉移細胞發(fā)育[99]的調控,調節(jié)小麥的抽穗期[100]。GsWRKY20正調控開花反應,通過調控開花相關基因和花分生組織基因的表達來促進植物開花過程[101]。同樣,芒草(Miscanthus)的MlWRKY12轉錄因子也被報道控制開花[102]。WRKY還參與到了大豆葉片脫落的器官極性和細胞命運的轉錄調控中[103]。
我們研究發(fā)現,AtWRKY25很有可能對ABA調控種子萌發(fā)和萌發(fā)后生長有拮抗作用[104]。WRKY40通過直接抑制ABA敏感基因例如ABI5的轉錄,作為ABA響應途徑的中心轉錄抑制子來起作用[106]。AtWRKY41通過直接調控ABI3在成熟種子中的表達來控制早期的種子休眠和熱抑制[107],CaWRKY6可以激活CaWRKY40,使其作為一個正調控因子調節(jié)Ralstonia solanacearum抗性和對熱的耐受性[108]。WRKY參與到水稻葉片早衰和種子休眠中,通過對WRKY的上調表達來激活信號轉導[109]。在在P.trichocarpa中約有100個WRKY基因,他們中的大部分都可以被JA、SA、冷脅迫、干旱脅迫、鹽脅迫或者傷口脅迫所誘導[110]。
AtWRKY6、AtWRKY22、AtWRKY53參與到植物衰老過程調控中[111-113]。WRKY53被報道加快了葉片的衰老過程[114]。AtWRKY54、AtWRKY57和AtWRKY70 同樣在葉片衰老中起調控作用[115]。我們的研究結果顯示AtWRKY57在JA誘導的衰老過程中,作為一個關節(jié)點來調控生長素和JA的信號轉導過程[116]。在水稻中過表達OsWRKY42導致葉片早衰[117]。之前報道過SA和H2O2可以刺激WRKY基因的表達,包括(WRKY-6、-42、-53、-71、-72、-77、-79和 -97)在葉片衰老中起到重要作用,并且這些WRKY轉錄因子在ospls1中的表達量明顯高于野生型[118,119]。在小麥基因組中,共有116個WRKY基因,其中30個確定為衰老相關WRKY基因,TaWRKY7、16、24、36、39、68、71、74、89、96、114、115和116 很可能是調節(jié)衰老的SAGs。在擬南芥中異位過表達TaWRKY7,在黑暗處理條件下觀察到葉片衰老過程的明顯加快;它還可以被ABA誘導,同時阻止了葉片的水分流失提高植株對干旱的忍耐性[120]。AtWRKY6可以直接結合到W-box上從而調控衰老誘導的類受體激酶基因的轉錄活性,atwrky6突變體和過表達AtWRKY6轉基因植株分別表現出早衰和延遲衰老的表型[121]。此外,在鐵缺失的條件下WRKY46轉錄因子通過調節(jié)液泡Fe轉運基因的表達,來調控Fe元素在植物體內從根到莖葉的轉運[122]。
WRKYs轉錄因子例如GaWRKY1、AaWRKY1、WRKY3、WRKY6和WRKY33都參與控制多種生物合成過程的調節(jié)中,包括棉子酚、青蒿素和植物抗毒素的生物合成調控[123-125]。在紫杉醇的生物合成過程中,從紅豆杉(Taxus chinensis)中分離的MeJA響應轉錄因子TcWRKYA1,在體外可以特異性地與兩個DBAT基因啟動子上W-box元件結合,而DBAT編碼紫杉醇生物合成過程中的關鍵酶[126]。CjWRKY1屬于IIc亞家族且響應JA信號,在生物堿異喹啉的生物合成過程中,過表達CjWRKY1能夠增強多種黃連素生物合成基因的轉錄激活[127]。雌性蛇麻草(Humulus lupulus L.)中的HlWRKY1調控蛇麻素生物合成的最后步驟,通過激活黃腐酚和苦酸生物合成的關鍵基因,例如查耳酮合酶H1,己酰苯合酶,異戊烯轉移酶1、1L和2,O-甲基轉移酶的轉錄來完成調控過程[128]。
4.1可變剪接
在病原體防御反應中,水稻WRKY62和 WRKY76轉錄因子的基因存在可變剪接。短的可變剪接OsWRKY62.2和OsWRKY76.2亞型可以彼此互作,也可以和全長的蛋白互作。OsWRKY62.2在植物中轉錄抑制作用減弱,OsWRKY62.2和OsWRKY76.2的剪接使得其對W-box的結合能力有所下降[129]。
4.2磷酸化
量光譜測定顯示,體外WRKY46能夠被MPK3磷酸化S168和S250位點。磷酸化位點的突變減慢了PAMP誘導的WRKY46降解的過程。在原生質體中過表達WRKY46可以增加PAMP響應提高植物基礎抗性[130]。WRKY8 和WRKY48作為植物對丁香假單胞菌(P. syringae)基礎防御的負調控因子又作為ETI的正調控因子,他們的生物突變體表現出抗性減弱和防御基因表達量的減少[131]。WRKY8、WRKY28和WRKY48的WRKY結構域可以直接被CPKs磷酸化,增強HR反應中WRKY46對細胞程序性死亡相關的標記基因啟動子區(qū)W-box元件的結合能力[132]。WRKY53可以直接被MAPK信號途徑的MEKK1蛋白磷酸化從而參與到植物的基礎防御反應的信號轉導過程中[133],WRKY53的磷酸化狀態(tài)可以加強靶基因的啟動和轉錄能力[134]。在響應B. cinerea 侵染的過程中,WRKY33可以被兩個明顯受病原菌誘導的MAPKs所磷酸化,啟動植物抗菌劑-植保素的生物合成[135]。在本生煙中MAPK介導NbWRKY8的磷酸化,NbWRKY8與AtWRKY33同源,參與PTI和ETI可以激活NADPH氧化酶的表達[136]。OsWRKY70可以被MAPK3和MAPK6磷酸化參與GA的生物合成,并且對植物生長和發(fā)育的動態(tài)平衡起重要作用。目前的報道顯示,在不同物種間MAPK是作為通用磷酸酶來磷酸化WRKY家族的蛋白質,并且最終作用到他們的靶基因上[137]。
WRKYs 參與到植物生命周期的多個方面,在植物正常的生命活動中有著重要的不可或缺的作用。通過調控植物細胞壁的合成、開花時間、種子儲藏物質代謝、種子萌發(fā)和休眠和植物衰老等過程參與植物的生長發(fā)育的各個階段。WRKYs和SA、JA等植物激素之間存在復雜的信號轉導調控網絡,并且在植物受到環(huán)境中的各種脅迫因素,例如干旱、鹽、缺氧、低溫、強光照等非生物脅迫的威脅和病原體、昆蟲、食草性或雜食性動物的入侵等生物脅迫的影響時,WRKY家族的轉錄調控蛋白通過激活或者抑制相關脅迫響應基因的轉錄激活,來增加植物對于環(huán)境的適應性和耐受性。WRKYs轉錄因子家族廣泛存在于綠色植物中,已經有關于不同物種中WRKYs相關作用的報道,但是大部分的調控網絡還不清晰,仍然還有很多內容需要進一步的研究證實和完善。
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(責任編輯 馬鑫)
WRKY Transcription Factors in Regulation of Stress Response in Plant
SUN Shu-hao YU Di-qiu
(Key Laboratory of Tropical Plant Resources and Sustainable Use,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Kunming 650223)
WRKY transcription factor families are characterized by a highly conserved WRKYGQK domain and involved in plant development,metabolism,answering to comprehensive biotic or abiotic stress. Recently,the research of WRKY transcription factors concentrate on stress response signaling network in different species. It reviewed progress of WRKYs members,and indicated that WRKY transcription factors play a heavy role in plant growth and regulating stress response. At the same time,there is less reported of WRKYs function in plant species besides model plant Arabidopsis thaliana and most of them focus on systematic research and analysis. In addition,numerous networks of WRKY transcription factors are still unclear.
WRKYs;biotic stress response;abiotic stress response;phytohormone
2016-08-30
國家自然科學基金項目(U1202264),云南省創(chuàng)新研究團隊(2014HC017)
孫淑豪,女,碩士,研究方向:植物逆境信號轉導;E-mail:sunshuhao@xtbg.ac.cn
余迪求,男,博士,研究方向:植物逆境生理;E-mail:ydq@xtbg.ac.cn