【摘要】：近些年來(lái),全球土壤鹽漬化問(wèn)題日益嚴(yán)重,影響了世界農(nóng)業(yè)的生產(chǎn)與發(fā)展。鹽脅迫作為一個(gè)主要的非生物脅迫,嚴(yán)重影響了植物的生長(zhǎng)發(fā)育。高鹽濃度導(dǎo)致植物離子穩(wěn)態(tài)失衡,滲透平衡紊亂,同時(shí)引起各種次級(jí)脅迫。植物則通過(guò)調(diào)控復(fù)雜的信號(hào)網(wǎng)絡(luò)來(lái)應(yīng)對(duì)鹽脅迫,包括Ca2+依賴(lài)型信號(hào)轉(zhuǎn)導(dǎo)途徑和Ca2+不依賴(lài)型信號(hào)轉(zhuǎn)導(dǎo)途徑。目前,利用分子生物學(xué)技術(shù)對(duì)鹽脅迫誘導(dǎo)基因的功能研究成為提高植物耐鹽性的重要方法。本實(shí)驗(yàn)以含有l(wèi)uciferase熒光蛋白的過(guò)表達(dá)擬南芥為材料,以200m M Na Cl為篩選條件做種子萌發(fā)實(shí)驗(yàn),獲得了鹽脅迫敏感基因HY2。HY2基因編碼了一個(gè)光敏色素膽素合成酶,負(fù)責(zé)質(zhì)體內(nèi)光敏色素生色團(tuán)的合成,并參與調(diào)控紅光及遠(yuǎn)紅光下的下胚軸伸長(zhǎng)。HY2蛋白N端的45個(gè)氨基酸有葉綠體轉(zhuǎn)運(yùn)肽的功能,且HY2蛋白定位在質(zhì)體里。后期結(jié)合突變體材料hy2從分子水平探討HY2基因在Na Cl信號(hào)轉(zhuǎn)導(dǎo)途徑下的功能。主要研究結(jié)果如下:(1)HY2基因在擬南芥中的表達(dá)無(wú)組織特異性,在根部表達(dá)量較低,花中表達(dá)量較高;(2)HY2基因在轉(zhuǎn)錄水平受鹽脅迫誘導(dǎo),且hy2突變體表現(xiàn)為對(duì)鹽不敏感,表明HY2可能是植物鹽脅迫信號(hào)通路中的一個(gè)負(fù)調(diào)控因子;HY2基因在蛋白水平不受鹽脅迫誘導(dǎo);(3)鹽脅迫應(yīng)答基因的表達(dá)分析結(jié)果表明,HY2通過(guò)不依賴(lài)ABA的方式來(lái)響應(yīng)鹽脅迫。同時(shí)在鹽脅迫下,hy2突變體能抑制DREB2A、KIN2等基因的表達(dá);(4)相對(duì)于Col4生態(tài)型,鹽脅迫對(duì)紅光下hy2突變體下胚軸伸長(zhǎng)的抑制程度較強(qiáng);(5)在生理生化水平,hy2突變體可以通過(guò)增加脯氨酸的積累,減少葉綠素的損失來(lái)提高植物的耐鹽性。
[Abstract]:In recent years, the problem of soil salinization in the world is becoming more and more serious, which affects the production and development of world agriculture. Salt stress, as a major abiotic stress, seriously affects the growth and development of plants. High salt concentration leads to imbalance of plant ion homeostasis, disturbance of osmotic balance and various secondary stresses. Plants respond to salt stress by regulating complex signal networks, including Ca2 dependent signal transduction pathways and Ca2 independent signal transduction pathways. At present, the study of the function of salt stress inducing genes by molecular biology has become an important method to improve the salt tolerance of plants. In this experiment, the overexpression Arabidopsis thaliana containing luciferase fluorescent protein was used as the material, and 200m M Na Cl was used as the screening condition for seed germination experiment. The salt stress sensitive gene HY2.HY2 gene encoded a Guang Min pigment choline synthase. Guang Min was responsible for the synthesis of pigment chromophore and involved in regulating the elongation of hypocotyls under red and far red light. The 45 amino acids at the N-terminal of HY2 protein had the function of chloroplast transporter peptide and HY2 protein was located in the plastids. The function of HY2 gene in Na Cl signal transduction pathway was studied at the molecular level with the mutant hy2 at late stage. The main results are as follows: (1) the expression of HY2 gene in Arabidopsis thaliana has no tissue specificity and is low in root and high in flower; (2) HY2 gene was induced by salt stress at the transcription level, and hy2 mutant was not sensitive to salt, suggesting that HY2 may be a negative regulator in plant salt stress signaling pathway, and HY2 gene is not induced by salt stress at protein level. (3) the results of salt stress response gene analysis showed that HY2 responded to salt stress by ABA independent. At the same time, hy2 mutant could inhibit the expression of DREB2A,KIN2 and other genes under salt stress. (4) compared with Col4 ecotype, salt stress inhibited the elongation of Hypocotyl of hy2 mutant under red light. (5) at the physiological and biochemical level, hy2 mutants can improve plant salt tolerance by increasing proline accumulation and reducing chlorophyll loss.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2016
【分類(lèi)號(hào)】：Q943.2

【相似文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前2條

1 張夢(mèng)龍;擬南芥HY2基因在NaCl信號(hào)轉(zhuǎn)導(dǎo)途徑中的功能研究[D];吉林大學(xué);2016年

2 蔣宇;HY2基因參與調(diào)控鋁抑制擬南芥根伸長(zhǎng)作用機(jī)制研究[D];吉林大學(xué);2014年

，

本文編號(hào)：2320143