發(fā)布時(shí)間：2018-05-14 14:40

  本文選題：獨(dú)行菜 + 低溫萌發(fā)��； 參考：《新疆師范大學(xué)》2017年碩士論文

【摘要】：獨(dú)行菜(Lepidium apetalum)是十字花科獨(dú)行菜屬的植物。生活在新疆北部的獨(dú)行菜具有典型的早春短命植物特征,并且能夠在早春寒冷天氣進(jìn)行萌發(fā)、生長,是良好的研究植物耐受低溫逆境的材料,但目前對其耐受低溫特性研究還很少。本文對獨(dú)行菜種子萌發(fā)及幼苗生長對低溫的耐受特性進(jìn)行了研究,并進(jìn)一步在轉(zhuǎn)錄組數(shù)據(jù)庫基礎(chǔ)上對獨(dú)行菜bHLH轉(zhuǎn)錄因子家族進(jìn)行了分析和相關(guān)基因的克隆,以期為闡述獨(dú)行菜種子萌發(fā)及幼苗生長耐受低溫的生理及分子機(jī)制提供研究基礎(chǔ)。主要結(jié)果如下:(1)獨(dú)行菜種子萌發(fā)對低溫脅迫的生理響應(yīng)的研究發(fā)現(xiàn),獨(dú)行菜種子在不同萌發(fā)階段對零下低溫均有良好的抗性,但隨萌發(fā)進(jìn)行抗性有所下降;萌發(fā)至中期的種子在4℃逆境中都能生存并生長,但生長速度顯著受到抑制;萌發(fā)中期獨(dú)行菜SOD、CAT活性與同工酶酶譜受低溫影響都很大:脅迫初期酶活性下降,短時(shí)間內(nèi)又迅速提高并維持在較高水平。(2)通過對獨(dú)行菜種子轉(zhuǎn)錄組測序結(jié)果進(jìn)行分析篩選后得到bHLH轉(zhuǎn)錄因子家族基因的序列共107條,去除冗余后得到其成員共83個(gè)。相對于低溫萌發(fā)停滯期的獨(dú)行菜種子,打破低溫停滯前后的獨(dú)行菜種子中有一條轉(zhuǎn)錄本c31476_g1在兩組中的表達(dá)量完全一致,其被注釋為轉(zhuǎn)錄因子bHLH27。(3)對獨(dú)行菜種子轉(zhuǎn)錄組bHLH類轉(zhuǎn)錄因子中相關(guān)基因進(jìn)行克隆和分析:其中序列c20009_g1(注釋為轉(zhuǎn)錄因子ICE1基因)cDNA全長序列為1503bp,命名為la ICE1,編碼一個(gè)分子量為54635.19KD、理論等電點(diǎn)pI為5.45、分子式為C2364H3742N688O758S22的蛋白質(zhì);序列c31476_g1(注釋為轉(zhuǎn)錄因子bHLH27)的cDNA全長序列為933bp,編碼一個(gè)分子量為76874.76KD、理論等電點(diǎn)pI為5.09、分子式為C2815H4699N933O1180S199的蛋白質(zhì);序列c17865_g1(注釋為轉(zhuǎn)錄因子bHLH7)的cDNA全長序列為765bp,編碼一個(gè)分子量為29180.96KD、理論等電點(diǎn)p I為4.65、分子式為C1277H2016N336O414S15的蛋白質(zhì)。綜合以上實(shí)驗(yàn)結(jié)果,對獨(dú)行菜種子耐受低溫萌發(fā)特性有了初步了解,而且對獨(dú)行菜種子轉(zhuǎn)錄組中bHLH轉(zhuǎn)錄因子家族基因的分布情況有了全面認(rèn)識,為進(jìn)一步的bHLH轉(zhuǎn)錄因子在獨(dú)行菜種子低溫萌發(fā)過程中的研究奠定基礎(chǔ)。
[Abstract]:Lepidium apetalumum is a plant of Cruciferae. The solitary vegetables living in the northern part of Xinjiang have typical early spring short-lived plant characteristics, and can germinate and grow in the cold weather of early spring. It is a good material for studying the tolerance of plants to low temperature stress. However, there are few studies on its tolerance to low temperature. In this paper, the characteristics of seed germination and seedling growth tolerance to low temperature were studied, and the bHLH transcription factor family and related gene cloning were further analyzed on the basis of transcriptional database. It is expected to provide a basis for studying the physiological and molecular mechanisms of seed germination and seedling growth tolerance to low temperature. The main results were as follows: (1) the physiological response of seed germination to low temperature stress showed that the seeds had good resistance to low zero temperature at different germination stages, but the resistance decreased with germination. The seeds from germination to middle stage could survive and grow under 4 鈩，

本文編號：1888311