宋興舜,孫麗娜,張秋艷,王瑞芳
(東北林業(yè)大學(xué)生命科學(xué)學(xué)院,哈爾濱 150040)
VDE基因在植物抗逆響應(yīng)中的功能
宋興舜,孫麗娜,張秋艷,王瑞芳
(東北林業(yè)大學(xué)生命科學(xué)學(xué)院,哈爾濱150040)
葉黃素循環(huán)存在于高等植物和綠色藻類,是保護(hù)植物光合機(jī)構(gòu)免受過剩光能破壞的重要機(jī)制。作為葉黃素循環(huán)關(guān)鍵酶,紫黃質(zhì)脫環(huán)氧化酶(VDE)可催化雙脫氧紫黃質(zhì)(V)脫環(huán)氧化成單環(huán)氧玉米黃質(zhì)(A)進(jìn)而生成玉米黃質(zhì)(Z),保護(hù)光合器官免受過剩光能破壞。VDE活性受多種因素調(diào)節(jié),在非生物脅迫下,植物多種葉綠素?zé)晒獾戎笜?biāo)均受影響,近期利用過表達(dá)、突變體與野生型植株對比研究進(jìn)一步揭示VDE基因在植物生長中的重要作用。文章綜述近年來有關(guān)VDE在植物抗逆生理中的功能研究進(jìn)展。
VDE;紫黃質(zhì)脫環(huán)氧化酶;非生物脅迫;光合參數(shù);熒光參數(shù)
宋興舜,孫麗娜,張秋艷,等.VDE基因在植物抗逆響應(yīng)中的功能[J].東北農(nóng)業(yè)大學(xué)學(xué)報,2016,47(9):85-90.
Song Xingshun,Sun Lina,Zhang Qiuyan,et al.Functions ofVDEin plant response to stresses[J].Journal of Northeast Agricultural University,2016,47(9):85-90.(in Chinese with English abstract)
植物生長過程受多種機(jī)制調(diào)節(jié),光作為綠色植物生長基本能量來源對植物生長起重要作用。綠色植物通過光合作用將光能轉(zhuǎn)變成化學(xué)能儲存并合理利用。為提高光合利用率,植物自身利用調(diào)節(jié)保護(hù)系統(tǒng)適應(yīng)光能強(qiáng)弱變化[1]。弱光下,植物盡可能將光能轉(zhuǎn)變成自身可利用能量;強(qiáng)光下,植物吸收的光能超過自身所需能量,不能促進(jìn)自身光合作用,反而破壞光合機(jī)構(gòu),即光抑制。過剩光能被葉綠素吸收引起三重態(tài)葉綠素(3Chl)產(chǎn)生,將能量運(yùn)輸至基態(tài)O2,產(chǎn)生高度有害的單線氧(1O2)甚至其他活性氧[2-3]。光系統(tǒng)受體終端過剩的光能可通過Mehler反應(yīng)產(chǎn)生有毒害作用的活性氧[4]。早期研究表明,暴露在脅迫環(huán)境下會增加細(xì)胞內(nèi)活性氧水平,抑制PSⅡ修復(fù),這是光抑制主要原因。為避免或減輕抑制作用,植物啟動多種防御機(jī)制,其中葉黃素循環(huán)是保護(hù)植物光合機(jī)構(gòu)免受過剩光能破壞的重要機(jī)制[5]。葉黃素循環(huán)是1957年由Sapozhnikov等發(fā)現(xiàn)。該循環(huán)有三種葉黃素參與,分別是雙環(huán)氧紫黃質(zhì)V、單環(huán)氧玉米黃質(zhì)A和玉米黃質(zhì)Z。在植物吸收過剩光能時,雙環(huán)氧紫黃質(zhì)在紫黃質(zhì)脫環(huán)氧化酶(VDE)作用下脫環(huán)氧化成單環(huán)氧玉米黃質(zhì)生成玉米黃質(zhì);在暗處,玉米黃質(zhì)在玉米黃質(zhì)環(huán)氧化酶(ZEP)作用下重新環(huán)化成單環(huán)氧玉米黃質(zhì)生成雙環(huán)氧紫黃質(zhì),自然界中很多環(huán)境因子均會影響該循環(huán)(見圖1)。
循環(huán)中Z含量增加可提高植株抗氧化能力[6]。研究發(fā)現(xiàn)Z的增加主要有三種作用:①通過熱耗散過程在吸收并傳遞光能的色素分子PSⅡ天線色素上將過剩激發(fā)能轉(zhuǎn)變?yōu)闊崮埽?-10];②通過NPQ (Non-photochemical quenching,非光化學(xué)猝滅)獨(dú)立過程建立起光氧化脅迫耐受性,將能量以熱能形式放出,可保護(hù)類囊體膜脂質(zhì)免受氧化損害[11-13];③降低補(bǔ)光葉綠素天線大小,并降低該膜流動性,以減少在類囊體內(nèi)活性氧的滲透[12,14]。而VDE活性增強(qiáng)將導(dǎo)致Z增加,表明VDE在葉黃素循環(huán)中起重要作用。
圖1 葉黃素循環(huán)Fig.1Xanthophyll cycle
1.1VDE基本結(jié)構(gòu)特征
1996年Bugos等首先從萵苣中克隆VDE全長cDNA,編碼473個氨基酸,其中轉(zhuǎn)運(yùn)肽長125個氨基酸[15]。相繼從番茄、小麥、水稻、菠菜、毛竹、茶樹、枸杞等[16-21]植物中克隆VDE基因。其分子質(zhì)量約為43 ku,等電點(diǎn)為5.4。VDE是一種水溶性酶,存在高等植物類囊體腔內(nèi)[22],光能促進(jìn)跨類囊體膜pH梯度建立,由水解產(chǎn)生大量H+和PQ(質(zhì)體醌)庫所輸入的H+會引起類囊體腔內(nèi)pH下降,在pH<6.0時,VDE結(jié)合到類囊體膜上后被激活具有催化作用。由于VDE基因中間脂質(zhì)蛋白類似區(qū)域一致性不高,但其晶體結(jié)構(gòu)中均含有高度保守的折疊模式,Bugos等將VDE劃分到脂質(zhì)蛋白類似家族[23]。鑒定該酶屬于脂質(zhì)運(yùn)載蛋白家族成員,具有結(jié)合和轉(zhuǎn)運(yùn)疏水小分子的特征區(qū)域。該蛋白在不同物種中顯示有三個很強(qiáng)的同源結(jié)構(gòu)域[23-24]:①N-末端有一個半胱氨酸富集區(qū),是VDE的活性位點(diǎn)[25],二硫蘇糖醇(DTT)的抑制位點(diǎn);②中部有一個脂轉(zhuǎn)運(yùn)蛋白信號區(qū),可能是雙環(huán)氧紫黃質(zhì)和MGDG結(jié)合位點(diǎn),而MGDC是VDE蛋白發(fā)揮催化功能的必需脂類。因此,此區(qū)域是對VDE活性最有效的脂質(zhì)區(qū);③C-端為谷氨酸富集區(qū),含有大量負(fù)電荷,是VDE與類囊體膜結(jié)合部位。與其他脂質(zhì)蛋白類似,VDE具有3個高度保守被稱為SCR (Structurally conserved regions)的區(qū)域,二級結(jié)構(gòu)具有八個反向平行的β-折疊結(jié)構(gòu)[19]。
通過植株不同組織VDE相對表達(dá)水平研究發(fā)現(xiàn),在植株成熟葉片中VDE表達(dá)量最多,而根和果中表達(dá)量最低,VDE表達(dá)多集中在光合組織部位[17,25-27]。李欣、Li等通過構(gòu)建CsVDE-GFP載體,利用GFP熒光標(biāo)記在黃瓜原生質(zhì)體中亞細(xì)胞定位,表明CsVDE蛋白表達(dá)在黃瓜原生質(zhì)體的葉綠體上,用免疫膠體金方法證實(shí)該結(jié)論[19,26]。
1.2VDE活性調(diào)節(jié)
VDE活性受pH、AsA(抗壞血酸)、V的可利用性、溫度、脂質(zhì)結(jié)構(gòu)、UV-B、DTT(二硫蘇糖醇)等影響。VDE可根據(jù)類囊體腔內(nèi)pH的不同結(jié)合到類囊體膜上或釋放出來[28]。在體內(nèi),VDE最適pH為4.8,在體外,VDE最適pH為5.2,當(dāng)pH≥7.0時,VDE將以自由態(tài)形式存在,當(dāng)pH為6.6時,一般的VDE分子結(jié)合到類囊體膜上,在研究VDE酶釋放與pH關(guān)系時發(fā)現(xiàn),VDE定位于內(nèi)囊體膜內(nèi)側(cè),與類囊體膜結(jié)合后方可發(fā)揮作用[29]。脫環(huán)氧化作用須有AsA參與,AsA是調(diào)節(jié)VDE環(huán)化作用與活性的內(nèi)源電子供應(yīng)體,是VDE酶底物之一[23],VDE酶受AsA濃度調(diào)節(jié)[30],當(dāng)植物遇到低溫或強(qiáng)光脅迫時,可通過提高AsA濃度適應(yīng)這種逆境[31]。V可利用性調(diào)節(jié)脫環(huán)氧化作用,一般情況下植物體內(nèi)只有約60%V轉(zhuǎn)化為A和Z[32],但V的轉(zhuǎn)化效率可隨強(qiáng)光處理時間而提高[33]。VDE酶活性也受溫度影響,可很大程度影響V的利用性和轉(zhuǎn)化效率,后來研究發(fā)現(xiàn)在5℃下Z形成受嚴(yán)重抑制。另外研究發(fā)現(xiàn)VDE酶活性與V和MGDG比例有關(guān)。DTT是VDE酶專一抑制劑,低濃度DTT可強(qiáng)烈抑制VDE酶活性[34]。UV-B輻射使VDE酶失活,可抑制PSⅡ活性,并降低V可利用性[35]。此外,VDE亞基紫黃質(zhì)和單半乳糖甘油二酯(MGDG)也對VDE活性起重要作用[36]。
2.1VDE基因?qū)?qiáng)光脅迫的響應(yīng)
植物在適宜光照條件下,隨葉綠素吸收光能增加,固定CO2和光合速率均會提高,但光照過度卻會抑制光合作用甚至導(dǎo)致光合機(jī)構(gòu)氧化損傷[37-38]。在高光下,植物生長和產(chǎn)量會大大受損,高等植物中PSⅡ最大光化學(xué)效率降低是光抑制的重要特征。野生型CsVDE基因在不同光照下對比顯示:強(qiáng)光下VDE基因響應(yīng)更快速,光強(qiáng)度增加使NPQ、(A+Z)/(V+A+Z)比值增加,而Fv/Fm和Pn均降低,其趨勢為:強(qiáng)光(1 200 μmol·m-2·s-1)>正常光(500 μmol·m-2·s-1)>低光(100 μmol·m-2·s-1)。相關(guān)研究表明,葉黃素循環(huán)色素池(V+A+Z)在強(qiáng)光下也會有所增加[39]。對于轉(zhuǎn)基因植株來說,強(qiáng)光脅迫下,反義轉(zhuǎn)基因植株中(V+A+Z)、(A+Z)/(A+ Z+V)和NPQ有所升高,F(xiàn)v/Fm有所下降,且對反義轉(zhuǎn)基因植株來說,強(qiáng)光下其NPQ、Fv/Fm和(A+ Z)/(V+A+Z)變化均明顯低于野生型。高光脅迫下,Pn和Fv/Fm在WT中減少量要明顯高于轉(zhuǎn)基因植株,低溫與高光脅迫下,NPQ、(A+Z)/(V+A+Z)逐漸上升,但過表達(dá)植株增加程度>野生植株>抑制表達(dá)植株[16,26]。過表達(dá)植株中高的NPQ和(A+Z)/ (V+Z+A)表明轉(zhuǎn)基因植株比野生型植株耗散更多能量,對光合器官提供有效保護(hù)。對于轉(zhuǎn)基因煙草中熒光參數(shù)日變化分析發(fā)現(xiàn),F(xiàn)v/Fm在上午隨光強(qiáng)增加而下降,13:00達(dá)最小值,之后逐漸上升;NPQ與FO從上午到13:00呈上升趨勢,13:00達(dá)最大值,之后逐漸降低。VDE表達(dá)可受溫度和光照日變化調(diào)節(jié),VDE過表達(dá)增加脫環(huán)氧化水平并有效緩解高光和低溫脅迫下PSⅠ和PSⅡ的光抑制[26]??傊?,脅迫下葉黃循環(huán)循環(huán)各組分及葉綠素?zé)晒鈪?shù)變化表明,VDE在避免植物因吸收過剩光能產(chǎn)生的損害中起重要作用。
2.2VDE基因?qū)Ω珊得{迫的響應(yīng)
干旱是制約農(nóng)作物生長發(fā)育主要因素之一,我國約有1/3可耕地處在干旱或半干旱地區(qū)[40]。對于植株自然條件失水干旱下葉片中VDE基因表達(dá)量分析顯示,VDE轉(zhuǎn)錄水平在干旱條件下逐漸升高,推測植物在干旱脅迫下自身機(jī)能受損,隨干旱時間延長及程度加重,自身啟動由VDE催化的葉黃素循環(huán)途徑抵御不適的外界環(huán)境。輕度干旱脅迫下,對葉片光化學(xué)效率影響小,隨干旱時間延長程度加重,光化學(xué)效率明顯下降,相反,NPQ明顯上升,因?yàn)檫@種脅迫下,產(chǎn)生過多光能,只能通過熱耗散形式釋放多余能量,才可減緩自身光抑制。檢測到脫環(huán)氧化速率(A+Z)/(V+A+Z)增加;早期研究表明,干旱會引起葉黃素循環(huán)色素池容量增加,干旱脅迫會使A和Z含量增加[41-43]。植物生長調(diào)節(jié)劑可通過響應(yīng)脅迫在一定程度上緩解環(huán)境變化帶給植物的各種損害,脫落酸(ABA)是其中之一[44-45],干旱下能引起ABA積累,導(dǎo)致氣孔關(guān)閉,離子向木質(zhì)部運(yùn)輸增強(qiáng)。Guan等通過干旱誘導(dǎo)內(nèi)源ABA研究枸杞VDE基因正反饋調(diào)節(jié)[17]。數(shù)據(jù)表明,分別對枸杞幼苗進(jìn)行abamineSG(ABA積累抑制劑)、干旱及abamineSG+干旱處理下,單獨(dú)abam?ineSG對ABA和葉綠素影響小,而在二者雙重處理下ABA增加量與葉綠素減少量明顯高于單獨(dú)干旱處理,相應(yīng)VDE表達(dá)量與ABA變化趨勢基本一致。相同處理下監(jiān)測野生型與轉(zhuǎn)基因擬南芥最大光合速率、脫環(huán)氧化速率及NPQ,研究發(fā)現(xiàn)干旱下VDE基因缺失使擬南芥抽薹和開花時間提前,氣孔導(dǎo)度及蒸騰速率降低,呼吸作用受抑制,非光化學(xué)猝滅、最大光化學(xué)效率降低[46],突變體植株萎蔫程度更高,成活率更低。
2.3VDE基因?qū)Φ蜏孛{迫響應(yīng)
低溫是限制對光敏感植物活性重要因素。低溫脅迫下植物體內(nèi)發(fā)生系列適應(yīng)性變化,包括組織結(jié)構(gòu)和生理生化變化[47]。低溫對葉綠體和PSⅡ反應(yīng)中心產(chǎn)生影響,與低溫下植物光合活性下降有關(guān)。脅迫下引發(fā)明顯PSⅡ和PSⅠ光抑制,PSⅠ相對PSⅡ敏感性要高[48-49],說明葉黃素循環(huán)色素存在于PSⅡ和PSⅠ[50-51]。低溫脅迫下(4℃),可氧化的P7100顯著下降[25],因?yàn)榈蜏叵掠衩S質(zhì)能影響膜的流動性并減少質(zhì)體醌再次氧化[52-54],對于轉(zhuǎn)基因型植株而言,可氧化P7100比野生型降低的更緩慢[25],由于在轉(zhuǎn)基因植物中玉米黃質(zhì)增加能保護(hù)脂質(zhì)過氧化并增加PSⅠ穩(wěn)定性,或是轉(zhuǎn)基因植株中玉米黃質(zhì)增加可終止更多活性氧。脅迫下,植物NPQ、(A+Z)/(V+A+Z)顯著上升,而Pn、Fv/Fm顯著下降,表明葉黃素循環(huán)和NPQ在保護(hù)光合器官免受損害中起關(guān)鍵作用。對于轉(zhuǎn)基因植株而言,F(xiàn)v/Fm下降幅度明顯低于野生型植株,重新放回室溫后,所有植株Fv/Fm均可恢復(fù)原有水平,VDE過表達(dá)促進(jìn)葉黃素循環(huán)脫氧化作用,脫環(huán)氧化狀態(tài)(Z+A)/(V+Z+A)升高。而VDE缺失突變體,NPQ和(Z+A)/(V+Z+A)比值升高程度低于野生型植株,Pn、Fv/Fm下降幅度均大于野生型植株。分析VDE低溫表達(dá)量,發(fā)現(xiàn)CsVDE在低溫條件下表達(dá)量先升后降。這些結(jié)果表明,VDE在減緩光抑制中起重要作用。
2.4VDE基因?qū)}脅迫的響應(yīng)
鹽脅迫下VDE響應(yīng)研究較少,研究表明,隨鹽濃度增加,酶活逐漸升高,嚴(yán)重鹽脅迫下,VDE活性降低,(A+Z)/(V+A+Z)不斷上升,NPQ和qE增加表明葉黃素循環(huán)色素脫環(huán)氧化程度增加有利于能量耗散。在與轉(zhuǎn)基因植株對比中發(fā)現(xiàn),鹽脅迫下,野生型中光抑制程度更嚴(yán)重,丙二醛(MDA)積累明顯增加,與野生型相比,轉(zhuǎn)基因植株增加程度略小。
隨著對葉黃素循環(huán)研究加深,其作用機(jī)制已明確。近年來,已克隆有關(guān)葉黃素類物質(zhì)合成相關(guān)酶的編碼基因,為深入認(rèn)識熱耗散及抗性關(guān)系分子機(jī)制提供基礎(chǔ)。Gao等在煙草中過量表達(dá)擬南芥VDE顯著提高高光強(qiáng)下葉黃素循環(huán)活性和NPQ[16]。擬南芥中真核翻譯起始因子elFiso4G為調(diào)節(jié)紫黃質(zhì)脫環(huán)氧化酶表達(dá)必需[55]。VDE活性受多因素調(diào)節(jié),如pH、抗壞血酸、紫黃質(zhì)的可利用性、溫度、脂質(zhì)結(jié)構(gòu)、UV-B、DTT等。非生物脅迫下,VDE表達(dá)量、熒光參數(shù)與光合作用參數(shù)均有顯著變化。獲得過表達(dá)與突變體,轉(zhuǎn)基因植株與野生型植株內(nèi)在與外在出現(xiàn)明顯差異,而對非生物脅迫下各指標(biāo)測定顯示VDE基因作用,為深入研究VDE作用機(jī)制提供基礎(chǔ)。
Demming等發(fā)現(xiàn)玉米黃質(zhì)存在與過剩光能的耗散有關(guān)以來[56],研究發(fā)現(xiàn),玉米黃質(zhì)參與非輻射能量耗散[57],但其內(nèi)部分子機(jī)理尚不清楚。目前對于葉黃素循環(huán)研究較多,但是對干旱脅迫下葉黃素循環(huán)組分對植物抗逆境影響研究較少;研究大多集中在簡單生理指標(biāo)與酶活性水平上,內(nèi)部作用機(jī)制研究不夠透徹;試驗(yàn)材料大多集中在草本等小型植物,很少選取林木與果樹,研究局限性很大。同時,ABA介導(dǎo)植物體對多種環(huán)境脅迫應(yīng)答,干旱、低溫、高鹽等環(huán)境脅迫均可導(dǎo)致植物體內(nèi)ABA積累。高等植物ABA主要是以類胡蘿卜素為前體,經(jīng)間接途徑合成。ABA合成發(fā)生在質(zhì)體和細(xì)胞質(zhì)中,在擬南芥中編碼ZEP,ZEP催化玉米黃素和環(huán)氧玉米黃素環(huán)氧化作用,產(chǎn)生全反構(gòu)象紫黃素。與野生型相比,擬南芥ABA缺陷突變體中新黃素含量降低而紫黃素含量增加[58],這表明AtABA4參與紫黃素到新黃素的轉(zhuǎn)化。ZEP與VDE同為葉黃素循環(huán)關(guān)鍵酶,ZEP變化將引起VDE改變,因而推測ABA與VDE可能存在間接甚至直接聯(lián)系。VDE與ABA代謝途徑中相關(guān)蛋白相互作用有待深入研究。
[1]周小龍.普通煙草紫黃質(zhì)脫環(huán)氧化酶基因的克隆和功能分析[D].鄭州:鄭州大學(xué),2013.
[2]Asada K,Takahashi M.Production and scavenging of active oxy?gen in photosynthesis[J].Photoinhibition,1987(9):227-287.
[3]Niyogi K K.Photoprotection revisited:Genetic and molecular ap?proaches[J].Annual Reviewof Plant Biology,1999,50(1):333-359.
[4]Asada K.The water-water cycle in chloroplasts:scavenging of ac?tive oxygen and dissipation of excess photons[J].Annual Review of Plant Physiology and Plant Molecular Biology,1999,50(1):601-639.
[5]Takahashi S,Murata N.How do environmental stresses accelerate photoinhibition?[J].Trends in Plant Science,2008,13:178-182.
[6]Havaux M,Dall'Osto L,Bassi R.Zeaxanthin has enhanced antioxi?dant capacity with respect to all other xanthophylls in Arabidopsis leaves and functions independent of binding to PSⅡantennae[J]. Plant Physiology,2007,145(4):1506-1520.
[7]Horton P,Wentworth M,Ruban A.Control of the light harvestingfunction of chloroplast membranes:The LHCII-aggregation mod?el for non-photochemical quenching[J].Febs Letters,2005,579:4201-4206.
[8]Ruban A V,Berera R,Ilioaia C,et al.Identification of a mecha?nism of photoprotective energy dissipation in higher plants[J].Na?ture,2007,450:575-578.
[9]Li X G,Li J Y,Zhao J P,et al.Xanthophyll cycle and inactivation of photosystem 2 reaction centers alleviating reducing pressure to photosystem 1 in morning glory leaves upon exposure to a shortterm high irradiance[J].Journal of Integrative Plant Biology,2007,49:1047-1053.
[10]Nilkens M,Kress E,Lambrev P H,et al.Identification of a slowly inducible zeaxanthin-dependent component of nonphotochemical quenching of chlorophyll fluorescence generated under steady stateconditionsinArabidopsis[J].BiochimBiophysActa,2010,1797:466-475.
[11]Baro L I,Do A D,Yamane T,et al.Zeaxanthin accumulation in the absence of a functional xanthophyll cycle protects Chlamydo?monas reinhardtii from photooxidative stress[J].Plant Cell,2003,15:992-1008.
[12]Havaux M,Dall'Osto L,Cuiné S,et al.The effect of zeaxanthin as the only xanthophyll on the structure and function of the photosyn?thetic apparatus in Arabidopsis thaliana[J].Journal of Biological Chemistry,2004,279(14):13878-13888.
[13]Johnson M P,Havaux M,Triantaphylidès C,et al.Elevated zea?xanthin bound to oligomeric LHCII enhances the resistance of Arabidopsis to photooxidative stress by a lipid-protective,antioxi?dant mechanism[J].Journal of Biological Chemistry,2007,282:22605-22618.
[14]Müller P,Li XP,Niyogi KK.Non-photochemical quenching:a re?sponse to excess light energy[J].Plant Physiology,2001,125:1158-1566.
[15]Bugos R C,Yamamoto H Y.Molecular cloning of violaxanthin deepoxidase from romaine lettuce and expression in Escherichia coli [J].Proceedings of the National Academy of Sciences,1996,93 (13):6320-6325.
[16]Gao S,Han H,F(xiàn)eng H L,et al.Overexpression and suppression of violaxanthin de-epoxidase affects the sensitivity of Photosys?tem II photoinhibition to high light and chillingstress in transgen?ic tobacco[J].Journal of Integrative Plant Biology,2010,52(3):332-339.
[17]Guan C,Ji J,Zhang X,et al.Positive feedback regulation of a Ly? cium chinense-derived VDE gene by drought-induced endoge?nous ABA,and over-expression of this VDE gene improve drought-induced photo-damage in Arabidopsis[J].Journal of Plant Physiology,2015,175:26-36.
[18]Chen Z,Gallie D R.Violaxanthin de-epoxidase is rate-limiting for non-photochemical quenching under subsaturating light or during chilling in Arabidopsis[J].Plant Physiology and Biochemis?try,2012,58:66-82..
[19]李欣.黃瓜紫黃質(zhì)脫環(huán)氧化酶(CsVDE)基因及其啟動子克隆和功能分析[D].北京:中國農(nóng)業(yè)大學(xué),2014.
[20]Zhang J J,Ying J,Chang S H,et al.Cloning and expression analy?sis of violaxanthin de-epoxidase(VDE)cDNA in wheat[J].Acta Bitanica Sinica,2003,45(8):981-985.
[21]林榮呈,李良壁,匡廷云.水稻紫黃質(zhì)脫環(huán)氧化酶基因的克隆、體外表達(dá)及酶促反應(yīng)[J].科學(xué)通報,2002,47(06):449-451.
[22]Hager A.Lichtbedingte pH-erniedrigung in einem chloroplastenkompartiment als ursache der enzymatischen violaxanthin→zea?xanthin-umwandlung;Beziehungen zur photophosphorylierung [J].Planta,1969,89(3):224-243.
[23]Bugos R C,Hieber A D,Yamamoto H Y.Xanthophyll cycle en?zymes are members of the lipocalin family,the first identified from plants[J].Journal of Biological Chemistry,1998,273(25):15321-15324.
[24]Jahns P,Heyde S.Dicyclohexylcarbodiimide alters the pH depen?dence of violaxanthin de-epoxidation[J].Planta,1999,207(3):393-400.
[25]Han H,Gao S,Li B,et al.Overexpression of violaxanthin de-ep?oxidase gene alleviates photoinhibition of PSⅡand PSⅠin toma?to during high light and chilling stress[J].Journal of plant physiol?ogy,2010,167(3):176-183.
[26]Li X,Zhao W,Sun X,et al.Molecular cloning and characteriza?tion of violaxanthin de-epoxidase(CsVDE)in cucumber[J].Pub?lic Library of Science One,2013,8(5):e64383.
[27]Huang J L,Cheng L L,Zhang Z X.Molecular cloning and charac?terization of violaxanthin de-epoxidase(VDE)in Zingiber offici?nale[J].Plant Science,2007,172(2):228-235.
[28]匡廷云.光合作用原初光能轉(zhuǎn)化過程的原理與調(diào)控[J].南京:江蘇科學(xué)出版社,2003:7.
[29]Hager A,Holocher K.Localization of the xanthophyll-cycle en?zyme violaxanthin de-epoxidase within the thylakoid lumen and abolition of its mobility by a(light-dependent)pH decrease[J]. Planta,1994,192(4):581-589.
[30]Bratt C E,Arvidsson P O,Carlsson M,et al.Regulation of violax?anthin de-epoxidase activity by pH and ascorbate concentration [J].Photosynthesis Research,1995,45(2):169-175.
[31]Sch?ner S,Krause G H.Protective systems against active oxygen species in spinach:response to cold acclimation in excess light[J]. Planta,1990,180(3):383-389.
[32]Siefermann D,Yamamoto H Y.Properties of NADPH and oxygendependent zeaxanthin epoxidation in isolated chloroplasts:A transmembrane model for the violaxanthin cycle[J].Archives of Biochemistry and Biophysics,1975,171(1):70-77.
[33]Thayer S S,Bj?rkman O.Leaf xanthophyll content and composi?tion in sun and shade determined by HPLC[J].Photosynthesis Re?search,1990,23(3):331-343.
[34]Demmig-Adams B.Carotenoids and photoprotection in plants:a role for the xanthophyll zeaxanthin[J].Biochimica et Biophysica Acta(BBA)-Bioenergetics,1990,1020(1):1-24.
[35]Pfündel E E,Pan R S,Dilley R A.Inhibition of violaxanthin deep?oxidation by ultraviolet-B radiation in isolated chloroplasts and intact leaves[J].Plant Physiology,1992,98(4):1372-1380.
[36]Yamamoto H Y,Higashi R M.Violaxanthin de-epoxidase:Lipid composition and substrate specificity[J].Archives of Biochemistry and Biophysics,1978,190(2):514-522.
[37]Gamon J A,Pearcy R W.Photoinhibition in Vitis californica the role of temperature during high-light treatment[J].Plant Physiolo?gy,1990,92(2):487-494.
[38]辛惠卿,霍俊偉.環(huán)境脅迫對果樹光合作用的影響[J].東北農(nóng)業(yè)大學(xué)學(xué)報,2008,39(9):130-135.
[39]Schindler C,Lichtenthaler H K.Photosynthetic CO2-assimilation,chlorophyll fluorescence and zeaxanthin accumulation in field grown maple trees in the course of a sunny and a cloudy day[J]. Journal of Plant Physiology,1996,148(3):399-412.
[40]孟健男,于晶,蒼晶,等.PEG脅迫對兩種冬小麥苗期抗旱生理特性的影響[J].東北農(nóng)業(yè)大學(xué)學(xué)報,2011,42(1):40-44.
[41]Brugnoli E,Bj?rkman O.Growth of cotton under continuous salini?ty stress:influence on allocation pattern,stomatal and non-stoma?tal components of photosynthesis and dissipation of excess light energy[J].Planta,1992,187(3):335-347.
[42]Demmig B,Winter K,Krüger A,et al.Zeaxanthin and the heat dissipation of excess light energy in Nerium oleander exposed to a combination of high light and water stress[J].Plant Physiology,1988,87(1):17-24.
[43]Munné-Bosch S,Alegre L.The xanthophyll cycle is induced by light irrespective of water status in field-grown lavender(Lavan?dula stoechas)plants[J].Physiologia Plantarum,2000,108(2):147-151.
[44]李晶,張麗芳,焦健,等.低溫脅迫下外源ABA對玉米幼苗生長影響[J].東北農(nóng)業(yè)大學(xué)學(xué)報,2015,46(11):1-7.
[45]王軍虹,徐琛,蒼晶,等.外源ABA對低溫脅迫下冬小麥細(xì)胞膜脂組分及膜透性的影響[J].東北農(nóng)業(yè)大學(xué)學(xué)報,2014,45(10):21-28. [46]馬曉蕾.干旱下擬南芥vde基因的基礎(chǔ)功能分析[D].哈爾濱:東北林業(yè)大學(xué),2014.
[47]蒼晶,王艷梅,王興,等.根際澆灌ABA對冬小麥幼苗抗寒性的影響[J].東北農(nóng)業(yè)大學(xué)學(xué)報,2013,44(4):36-42.
[48]Sonoike K and Terashima I.Mechanism of the photo system I pho?toinhibition in leaves of Cucumis sativus L[J].Planta,1994,194:287-293.
[49]Havaux M,Davaud A.Photoinhibition of photosynthesis in chilled potato leaves is not correlated with a loss of photosystem-II activi?ty[J].Photosynthesis research,1994,40(1):75-92.
[50]Thayer S S,Bj?rkman O.Carotenoid distribution and deepoxida?tion in thylakoid pigment-protein complexes from cotton leaves and bundle-sheath cells of maize[J].Photosynthesis Research,1992,33(3):213-225.
[51]Lee A I,Thornber J P.Analysis of the pigment stoichiometry of pigment-protein complexes from Barley(Hordeum vulgare)(The xanthophyll cycle intermediates occur mainly in the light-harvest?ing complexes of photosystem I and photosystem II)[J].Plant Phys?iology,1995,107(2):565-574.
[52]Gruszecki W I,Strzalka K.Does the xanthophyll cycle take part in the regulation of fluidity of the thylakoid membrane?[J].Biochi?mica et Biophysica Acta(BBA)-Bioenergetics,1991,1060(3):310-314.
[53]Havaux M,Gruzecki W I.Heat-and light-induced chlorophyll a fluorescence changes in potato leaves containing high or low lev?els of the carotenoid zeaxanthin:Indications of a regulatory effect of zeaxanthin on thylakoid membrane fluidity[J].Photochemistry and Photobiology,1993,58(4):607-614.
[54]Havaux M.Carotenoids as membrane stabilizers in chloroplasts [J].Trends in Plant Science,1998,3(4):147-151.
[55]Chen Z,Jolley B,Caldwell C,et al.Eukaryotic translation initia?tion factor eIFiso4G is required to regulate violaxanthin de-epoxi?dase expression in Arabidopsis[J].Journal of Biological Chemis?try,2014,289(20):13926-13936.[56]Demmig B,Winter K,Krüger A,et al.Photoinhibition and zeaxan?thin formation in intact leaves a possible role of the xanthophyll cycle in the dissipation of excess light energy[J].Plant Physiolo?gy,1987,84(2):218-224.
[57]董高峰,陳貽竹,蔣躍明.植物葉黃素循環(huán)與非輻射能量耗散[J].植物生理學(xué)通訊,1999(2):141-144.
[58]North HM,F(xiàn)rey A,Boutin JP.Analysis of xanthophyll cycle gene expression during the adaptation of Arabidopsis to excess light and drought stress:Changes in RNA steady-state levels do not contribute to short-term responses[J].Plant Science,2005,169:115-124.
Functions ofVDEin plant response to stresses
SONG Xingshun,SUN Lina,ZHANG Qiuyan,WANG Ruifang
(School of Life Sciences,Northeast Forestry University,Harbin 150040,China)
The xanthophyll cycle exists in higher plants and green algae,which is considered to function as protecting plant photosynthetic apparatus from the damage of excessive light.Violaxanthin deepoxidase(VDE),a key enzyme in xanthophyll cycle,could catalyze the conversion of violaxanthin(V)via antheraxanthin(A)and then to zeaxalnthin(Z),protecting photosynthesis apparatus from photo damage. VDE activity was regulated by a variety of factors.It had been suggested that some factors,such as cholophyll fluorescence,were influenced by abiotic stresses.The recent investigations revealed the important role ofVDEin plant growth by overexpression,mutations of genes as well as wild type plants.In this review,we reviewed the recent research progress on functions of VDE in plant response to stresses.
VDE;violaxanthin de-epoxidase;abiotic stress;photosynthesis parameter;fluorescence parameter
Q943.2
A
1005-9369(2016)09-0085-06
2016-03-23
國家自然科學(xué)基金項目(30800876,31170569);中央高?;究蒲袠I(yè)務(wù)費(fèi)專項資金項目(2572015DA02,2572014EA04)
宋興舜(1978-),男,教授,博士,博士生導(dǎo)師,研究方向?yàn)橹参锬婢成砼c分子機(jī)制。E-mail:sfandi@163.com