本文選題：蘋果 + 異三聚體G蛋白��； 參考：《中國農(nóng)業(yè)科學(xué)》2017年03期

【摘要】：【目的】異三聚體G蛋白(Heterotrimeric G protein)作為植物生物體內(nèi)重要的信號(hào)轉(zhuǎn)導(dǎo)分子,在感受外界環(huán)境刺激、參與植物抗逆反應(yīng)和跨膜信號(hào)轉(zhuǎn)導(dǎo)等方面發(fā)揮著重要作用�？寺‘惾垠wG蛋白α亞基基因MdGPA1,并在煙草中過量表達(dá)MdGPA1,對(duì)其進(jìn)行生物學(xué)功能鑒定和生理指標(biāo)分析,為多年生木本植物響應(yīng)環(huán)境因子信號(hào)轉(zhuǎn)導(dǎo)過程中的分子機(jī)理研究提供參考�！痉椒ā勘狙芯恳浴吕O果(Malus×domestica‘Royal Gala’)為研究試材,利用同源序列比對(duì)和PCR技術(shù),克隆獲得MdGPA1。使用MEGA5.0構(gòu)建GPA1物種間系統(tǒng)進(jìn)化樹;利用qRT-PCR方法檢測(cè)該基因在蘋果受非生物脅迫誘導(dǎo)表達(dá)及組織特異性表達(dá)情況。構(gòu)建MdGPA1植物過表達(dá)載體,通過農(nóng)桿菌介導(dǎo)法轉(zhuǎn)化煙草葉片,比較干旱脅迫條件下野生型和轉(zhuǎn)基因株系的表型與生理指標(biāo),驗(yàn)證MdGPA1在植物干旱脅迫條件下的生物學(xué)功能�！窘Y(jié)果】克隆得到蘋果異三聚體G蛋白α亞基基因MdGPA1(基因序列號(hào):MDP0000881842),該基因長為1 173 bp,編碼390個(gè)氨基酸。進(jìn)化樹分析表明MdGPA1與白梨Pb GPA1親緣關(guān)系最近,同源性最高�；虮磉_(dá)分析顯示MdGPA1主要在葉片中表達(dá),在根系中的表達(dá)量次之,在莖和果實(shí)中的表達(dá)量較低。定量分析表明,該基因參與干旱、低溫和鹽等非生物逆境脅迫響應(yīng),在150 mmol·L~(-1)Na Cl、150 mmol·L~(-1)甘露醇、10%PEG和4℃脅迫條件下表達(dá)量明顯下調(diào),在5%H_2O_2脅迫處理下表達(dá)量明顯上調(diào)。在煙草中過量表達(dá)MdGPA1,發(fā)現(xiàn)MdGPA1轉(zhuǎn)基因煙草表現(xiàn)出對(duì)干旱敏感的表型特征,其葉片鮮重、葉綠素含量以及脯氨酸含量明顯低于野生型煙草。在地下部,MdGPA1轉(zhuǎn)基因煙草同樣表現(xiàn)出對(duì)干旱敏感的表型特征;其根系形態(tài)相比于野生型較小,干重也明顯低于野生型�！窘Y(jié)論】MdGPA1參與了植物感受外界環(huán)境刺激的過程,對(duì)干旱、低溫和鹽等非生物逆境脅迫都存在著不同程度的響應(yīng)。在煙草中異源表達(dá)MdGPA1后,提高了煙草對(duì)干旱的敏感性,轉(zhuǎn)基因煙草表現(xiàn)出不耐干旱的表型,受干旱脅迫比野生型煙草更為嚴(yán)重,說明MdGPA1在響應(yīng)植物抗旱脅迫中起著負(fù)調(diào)控作用。
[Abstract]:[objective] Heterotrimeric G protein, as an important signal transduction molecule in plant organisms, plays an important role in sensing environmental stimuli, participating in plant stress resistance and transmembrane signal transduction. The gene MdGPA1 was cloned and overexpressed in tobacco, and its biological function and physiological indexes were analyzed. [methods] MdGPA1 was cloned from 'Malus 脳 domestica'Royal Gala' by using homologous sequence alignment and PCR techniques. MEGA5.0 was used to construct the phylogenetic tree among GPA1 species, and qRT-PCR method was used to detect the induced expression and tissue specific expression of the gene in apple under abiotic stress. MdGPA1 plant overexpression vector was constructed and transformed into tobacco leaves by Agrobacterium tumefaciens. The phenotypic and physiological indexes of wild type and transgenic lines under drought stress were compared. To verify the biological function of MdGPA1 under drought stress, MdGPA1 (gene sequence number: MDP00881842) was cloned into Apple heterotrimer G protein 偽 subunit (gene sequence number: MDP0000881842). The gene length was 1 173bpand encoding 390 amino acids. Phylogenetic tree analysis showed that MdGPA1 had the closest genetic relationship with Pb GPA1 and had the highest homology. Gene expression analysis showed that MdGPA1 was mainly expressed in leaves, followed by roots, and lower in stems and fruits. Quantitative analysis showed that the gene was involved in the response to abiotic stresses such as drought, low temperature and salt, and was significantly down-regulated under 150 mmol L~(-1)Na CLC 150 mmol L ~ (-1) mannitol 10PEG stress and 4 鈩，

本文編號(hào)：1936506