本文選題：鋁脅迫　切入點(diǎn)：一氧化氮　出處：《河南師范大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：鋁脅迫是酸性土壤中限制植物正常生長(zhǎng)和農(nóng)作物產(chǎn)量的主要逆境因子,鋁毒害對(duì)植物最初和最顯著的一個(gè)特征就是抑制植物根的生長(zhǎng)。一氧化氮(NO)作為信號(hào)分子參與了多種生物脅迫和非生物脅迫響應(yīng),然而其在鋁脅迫中的調(diào)節(jié)作用仍不太清楚。作為戊糖磷酸途徑的限速酶之一,葡萄糖-6-磷酸脫氫酶(G6PDH)可以催化產(chǎn)生還原力NADPH。有研究報(bào)道,G6PDH參與了多種環(huán)境脅迫的抗逆性反應(yīng),然而關(guān)于其對(duì)鋁脅迫的響應(yīng)及其調(diào)節(jié)作用還未見報(bào)道。本研究以大豆為實(shí)驗(yàn)材料,探討了NO和G6PDH對(duì)鋁脅迫的響應(yīng)及其在鋁毒害下的調(diào)控機(jī)制。主要結(jié)果如下:1.低濃度鋁脅迫下NO對(duì)鋁毒害的調(diào)節(jié)作用鋁脅迫下,大豆幼苗根長(zhǎng)和根尖伸長(zhǎng)區(qū)細(xì)胞大小均受到抑制,膜脂過(guò)氧化程度增加,活性氧(H2O2和O2ˉ·)含量顯著升高;抗氧化劑BHA處理則緩解了鋁毒害引發(fā)的根生長(zhǎng)抑制和膜脂過(guò)氧化程度。表明鋁脅迫通過(guò)刺激根中活性氧(ROS)的累積,加深了膜脂過(guò)氧化的程度,從而導(dǎo)致氧化傷害,最終影響根尖伸長(zhǎng)區(qū)細(xì)胞的形態(tài)大小,造成根生長(zhǎng)抑制。鋁脅迫下,NO供體(SNP)處理減輕了鋁誘導(dǎo)的根伸長(zhǎng)抑制、ROS積累以及膜脂過(guò)氧化程度,而NO清除劑(PTIO)處理則進(jìn)一步加重了鋁毒害。進(jìn)一步研究結(jié)果顯示,鋁脅迫下SNP處理能顯著增強(qiáng)抗氧化酶(POD、CAT)活性、抗氧化劑(GSH和ASA)含量以及GSH-ASA循環(huán)系統(tǒng)中的關(guān)鍵酶(APX、GR、DHAR和MDHAR)活性,而PTIO處理則抑制了鋁誘導(dǎo)的抗氧化劑含量及抗氧化酶活性的增加。鋁脅迫處理顯著增加了大豆根中NO含量和硝酸還原酶(NR)活性,NR抑制劑處理則消除了鋁誘導(dǎo)的NO含量的增加,而一氧化氮合酶(NOS)抑制劑處理后,NO含量沒有明顯改變,表明鋁脅迫下NO的產(chǎn)生主要來(lái)自于NR途徑。這些結(jié)果說(shuō)明,鋁脅迫下NR介導(dǎo)產(chǎn)生的NO通過(guò)調(diào)節(jié)抗氧化酶活性以及GSH-ASA循環(huán)中的GSH和ASA含量來(lái)清除過(guò)量的ROS,進(jìn)而增強(qiáng)大豆對(duì)鋁毒害的耐受性。2.高濃度鋁脅迫下G6PDH對(duì)鋁毒害的調(diào)節(jié)作用高濃度鋁脅迫(≥200μM)處理能顯著增加大豆根中總G6PDH活性,并隨著鋁濃度的增加酶活性逐漸升高;同時(shí),胞質(zhì)G6PDH(Cyt-G6PDH)活性與總G6PDH活性的變化趨勢(shì)類似,而質(zhì)體G6PDH活性則沒有明顯改變,表明鋁脅迫引發(fā)的G6PDH活性的增加主要來(lái)源于Cyt-G6PDH。鋁脅迫下,G6PDH抑制劑(GN6P)處理緩解了鋁誘導(dǎo)的根生長(zhǎng)抑制、膜脂過(guò)氧化以及ROS的積累,表明G6PDH參與了鋁對(duì)大豆的毒害作用。進(jìn)一步研究結(jié)果顯示,NADPH氧化酶抑制劑(DPI)處理消除了鋁脅迫引發(fā)的ROS積累,表明鋁脅迫下ROS積累來(lái)自于NADPH氧化酶途徑。鋁脅迫下,GN6P處理降低了NADPH含量以及NADPH氧化酶活性,表明G6PDH調(diào)節(jié)了NADPH氧化酶的活性。隨后的研究結(jié)果顯示,鋁脅迫提高了Cyt-G6PDH活性及編碼基因(G6PDH1和G6PDH2)的表達(dá),SNP處理進(jìn)一步增強(qiáng)了其活性及基因表達(dá),PTIO處理則抑制了其活性及基因表達(dá),表明NO介導(dǎo)了鋁脅迫誘導(dǎo)的Cyt-G6PDH活性的增強(qiáng),該調(diào)節(jié)方式可能是通過(guò)增強(qiáng)G6PDH1和G6PDH2的基因表達(dá)實(shí)現(xiàn)的。此外,高濃度鋁脅迫下,NO含量顯著增強(qiáng),其產(chǎn)生途徑也是來(lái)源于NR途徑。這些結(jié)果說(shuō)明,鋁脅迫下由NO介導(dǎo)的Cyt-G6PDH通過(guò)調(diào)節(jié)NADPH氧化酶依賴的ROS的積累,使得大豆遭受氧化傷害,最終導(dǎo)致大豆根生長(zhǎng)抑制。綜上所述,鋁脅迫下,大豆幼苗能夠通過(guò)NR途徑產(chǎn)生NO,NO有兩方面的作用,一方面是相對(duì)低濃度鋁脅迫下,通過(guò)調(diào)節(jié)抗氧化酶活性和抗氧化劑含量來(lái)緩解鋁脅迫造成的氧化損傷和根長(zhǎng)抑制;另一方面,相對(duì)高濃度鋁脅迫下,NO能夠通過(guò)調(diào)節(jié)Cyt-G6PDH編碼基因的表達(dá)來(lái)增強(qiáng)Cyt-G6PDH活性,由此引發(fā)NADPH的累積和NADPH氧化酶活性的增強(qiáng),導(dǎo)致ROS的積累和氧化傷害程度的加深,最終引發(fā)根生長(zhǎng)抑制。
[Abstract]:Aluminum stress is the main stress factors limiting plant growth and crop production in acid soils, aluminum toxicity to plants initially and one of the most significant feature is the inhibition of root growth. Nitric oxide (NO) as a signal molecule involved in various biotic and abiotic stress response, but its role in regulating aluminum stress is still not clear. As one of the rate limiting enzyme of the pentose phosphate pathway, glucose -6- phosphate dehydrogenase (G6PDH) catalyzes the generation of reducing power of NADPH. studies have reported that G6PDH is involved in the reaction resistance of various environmental stresses, but on the aluminum stress response and its regulation has not been reported. This study takes soybean as experimental materials. Effects of NO and G6PDH in response to Al stress and the regulation mechanism of aluminum toxicity. The main results are as follows: 1. the low concentration of aluminum stress under the regulation of NO on aluminum toxicity in the presence of Al Under the stress, soybean seedling root length and root elongation zone cell size was inhibited, the degree of membrane lipid peroxidation increased reactive oxygen species (H2O2 and O2 - -) content increased significantly; antioxidant BHA treatment alleviated the inhibition and lipid growth caused by Al peroxidation. Root showed that aluminum stress by stimulating root activity oxygen (ROS) accumulation, enhance the membrane lipid peroxidation, resulting in oxidative damage, and ultimately affect the shape and size of cells of root elongation zone, resulting in root growth inhibition. Under aluminum stress, NO donor (SNP) treatment reduced the Al induced inhibition of root elongation, ROS accumulation and membrane lipid peroxidation the degree of NO and scavenger (PTIO) treatment was further aggravated the aluminum toxicity. Further study showed that SNP treatment could enhance the antioxidant enzymes (POD, CAT) Al stress activity of antioxidants (GSH and ASA) and the GSH-ASA content of key enzymes in the circulatory system (APX, GR, DHAR and MDHAR) activity increased, while PTIO treatment inhibited the antioxidant content and antioxidant enzyme activity induced by aluminum. Aluminum stress significantly increased NO content and nitrate reductase activity in Soybean (NR), NR inhibitor treatment eliminates the increase of NO content induced by aluminum, and nitric oxide synthase (NOS) inhibitor, did not significantly change the content of NO, NO showed that under aluminum stress generated mainly from the NR pathway. These results suggest that the lead under aluminum stress NO NR mediated by regulating the activity of antioxidant enzymes and the GSH-ASA loop in GSH and ASA content to remove the excess ROS, thus enhancing the tolerance of.2. the high concentration of aluminum to aluminum toxicity in Soybean under G6PDH stress on aluminum toxicity in the regulating effect of high concentrations of aluminum stress (more than 200 M) treatment significantly increased the total G6PDH of soybean root activity, and with the increase of the concentration of aluminum enzyme activity gradually increased; at the same time, cell G6PDH (Cyt-G6PDH) activity and the change trend of total G6PDH activity and G6PDH activity were similar, plastids did not change significantly, that caused the G6PDH activity of aluminum stress increase comes mainly from Cyt-G6PDH. under aluminum stress, G6PDH inhibitor (GN6P) treatment alleviated the Al induced root growth inhibition, membrane lipid peroxidation and ROS the accumulation suggests that G6PDH is involved in the toxic effects of aluminum on soybean. Further study showed that NADPH oxidase inhibitor (DPI) treatment to eliminate aluminum stress caused by the accumulation of ROS, suggesting that the accumulation from the NADPH oxidase pathway ROS under aluminum stress. Under aluminum stress, GN6P treatment reduced the NADPH content and NADPH oxidase activity, suggesting that G6PDH regulates the activities of NADPH. The results show that aluminum stress increased Cyt-G6PDH activity and encoding gene (G6PDH1 and G6PDH2) expression of SNP further enhances its activity and base Because the expression of PTIO inhibited the activity and gene expression, suggesting that NO mediated enhancement of aluminum stress induced Cyt-G6PDH activity, the regulation may be enhanced by G6PDH1 and G6PDH2 gene expression. In addition, the high concentration of Al stress, the NO content increased significantly, which is derived from the NR pathway methods. These results indicated that under aluminum stress mediated by NO Cyt-G6PDH by regulating NADPH oxidase dependent ROS accumulation, the soybean suffered oxidative damage, eventually leading to root growth inhibition. In conclusion, under aluminum stress, soybean seedlings can produce NO through NR pathway, NO has two effects, one is relative low concentration of aluminum stress by regulating antioxidant enzyme activity and antioxidant content to alleviate oxidative damage and root growth inhibition caused by aluminum stress; on the other hand, relatively high concentrations of aluminum stress, NO could adjust Cy The expression of t-G6PDH coding gene enhances Cyt-G6PDH activity, which results in the accumulation of NADPH and the enhancement of NADPH oxidase activity, resulting in the increase of ROS accumulation and oxidative damage, and finally the growth inhibition of root growth.

【學(xué)位授予單位】：河南師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：Q945.78;S565.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 王曉暉;劉曉;高博聞;張鐘秀;史社坡;屠鵬飛;;臘梅葡萄糖-6-磷酸脫氫酶(G6PDH1)基因的克隆及表達(dá)分析[J];中國(guó)中藥雜志;2015年21期

2 Chengliang Sun;Lijuan Liu;Yan Yu;Wenjing Liu;Lingli Lu;Chongwei Jin;Xianyong Lin;;Nitric oxide alleviates aluminum-induced oxidative damage through regulating the ascorbateglutathione cycle in roots of wheat[J];Journal of Integrative Plant Biology;2015年06期

3 曹明明;吳志明;婁群峰;阮氏清云;陳勁楓;;甜瓜屬野生種Cucumis hystrix Chakr.胞質(zhì)葡萄糖-6-磷酸脫氫酶基因的克隆與啟動(dòng)子結(jié)構(gòu)分析[J];南京農(nóng)業(yè)大學(xué)學(xué)報(bào);2013年02期

4 汪承潤(rùn);何梅;李月云;姜傳軍;田劉敏;王勤英;;植物體超氧陰離子自由基不同檢測(cè)方法的比較[J];環(huán)境化學(xué);2012年05期

5 袁明英;湯浩茹;于定群;張勇;;草莓G6PDH基因片段的克隆與序列分析[J];生物技術(shù)通報(bào);2010年10期

6 湯紅玲;李江;陳惠萍;;外源一氧化氮對(duì)香蕉幼苗抗冷性的影響[J];西北植物學(xué)報(bào);2010年10期

7 毛亞斌;魏小紅;;外源NO對(duì)干旱脅迫下板藍(lán)根葉片氧化損傷的保護(hù)作用[J];草業(yè)科學(xué);2010年06期

8 謝國(guó)生;師瑞紅;龐貞武;蔡克桐;;鋁脅迫下水稻幼苗根系的生理特性[J];應(yīng)用生態(tài)學(xué)報(bào);2009年07期

9 詹潔;寇瑞杰;李創(chuàng)珍;何虎翼;何龍飛;;鋁脅迫對(duì)花生根尖線粒體膜生理特性的影響[J];作物學(xué)報(bào);2009年06期

10 張小莉;王鵬程;宋純鵬;;植物細(xì)胞過(guò)氧化氫的測(cè)定方法[J];植物學(xué)報(bào);2009年01期

相關(guān)會(huì)議論文 前1條

1 林善枝;張志毅;;在甜楊幼苗抗凍性的低溫誘導(dǎo)中鈣對(duì)鈣調(diào)蛋白及其可能調(diào)節(jié)酶類的效應(yīng)[A];持續(xù)發(fā)展，，再創(chuàng)輝煌——中國(guó)林學(xué)會(huì)林木遺傳育種分會(huì)第五屆年會(huì)文集[C];2002年

相關(guān)博士學(xué)位論文 前2條

1 趙秀峰;一氧化氮對(duì)水稻幼苗鎘毒害的緩解效應(yīng)及其生理機(jī)制[D];南京農(nóng)業(yè)大學(xué);2012年

2 鞏慧玲;植物愈傷組織對(duì)高溫脅迫的生理響應(yīng)及G6PDH對(duì)高溫適應(yīng)的調(diào)節(jié)機(jī)理研究[D];蘭州大學(xué);2011年

相關(guān)碩士學(xué)位論文 前1條

1 楊利娟;NO和乙烯在鋁脅迫抑制綠豆根伸長(zhǎng)中的作用及其相互關(guān)系研究[D];陜西師范大學(xué);2009年

本文編號(hào)：1613426