本文選題：玉米　切入點(diǎn)：熱激轉(zhuǎn)錄因子ZmHsf　出處：《農(nóng)業(yè)生物技術(shù)學(xué)報(bào)》2017年09期 　論文類型：期刊論文

【摘要】：植物熱激轉(zhuǎn)錄因子(heat shock transcription factor,Hsf)能夠與熱激蛋白基因啟動(dòng)子區(qū)域的熱激元件結(jié)合而直接啟動(dòng)熱激反應(yīng),因此成為熱脅迫下基因轉(zhuǎn)錄激活信號(hào)轉(zhuǎn)導(dǎo)通路中重要的調(diào)控因子。前人推測玉米(Zea mays)中至少有30個(gè)Hsf家族成員,其中A族18個(gè),A2亞族4個(gè)。本實(shí)驗(yàn)室在前期對(duì)A1亞族Zm Hsf06結(jié)構(gòu)、特性及其抗旱耐熱性功能研究的基礎(chǔ)上,采用同源克隆技術(shù),從玉米幼葉中克隆獲得A2亞族基因ZmHsf04(Gen Bank登錄號(hào):GRMZM2G010871_P01)的完整編碼序列,序列全長1 074 bp,編碼357個(gè)氨基酸殘基。蛋白質(zhì)結(jié)構(gòu)包含Hsf家族DNA結(jié)合結(jié)構(gòu)域,含有核定位信號(hào)(KRKELEDTISKKRRR)、核輸出信號(hào)(LAQQLGYL)和激活結(jié)構(gòu)域(LKMFESGVLN)等完整的功能結(jié)構(gòu)域。蛋白序列與高粱(Sorghum bicolor)SORBIDRAFT_01g021490的同源性最高,達(dá)90%。熒光定量分析表明,正常生長條件下ZmHsf04在玉米多個(gè)組織器官中表達(dá),幼嫩花粉中表達(dá)較高,約為幼嫩根系對(duì)照的16倍;ZmHsf04的表達(dá)水平受42℃熱脅迫和外源脫落酸(abscisic acid,ABA)顯著上調(diào),最高表達(dá)量達(dá)正常對(duì)照的340倍,葉片峰值出現(xiàn)的時(shí)間分別為30 min和24 h;ZmHsf04也受水楊酸(SA)和H2O2上調(diào)表達(dá),上調(diào)幅度低于熱處理,最高表達(dá)量不超過12倍,顯著低于熱激或ABA處理,峰值出現(xiàn)相對(duì)滯后;用SA和H2O2分別預(yù)處理再熱激,ZmHsf04的表達(dá)水平無明顯差異。通過在洋蔥(Allium cepa)表皮細(xì)胞中瞬時(shí)表達(dá)并觀察綠色熒光蛋白(green fluorescence protein,GFP)熒光發(fā)現(xiàn),ZmHsf04定位于細(xì)胞核。通過將ZmHsf04轉(zhuǎn)化酵母(Saccharomyces cerevisiae)并進(jìn)行50℃水浴熱脅迫處理發(fā)現(xiàn),ZmHsf04在酵母中可被半乳糖誘導(dǎo)蛋白表達(dá),熱脅迫同時(shí)降低正常和轉(zhuǎn)ZmHsf04酵母的生長勢,但與轉(zhuǎn)空載體對(duì)照相比,轉(zhuǎn)ZmHsf04基因酵母表現(xiàn)更強(qiáng)的耐熱性。研究結(jié)果表明,ZmHsf04在植株花粉發(fā)育和熱脅迫響應(yīng)過程中可能發(fā)揮重要的調(diào)控功能。該研究為進(jìn)一步解析ZmHsf04的功能及其調(diào)控機(jī)制提供理論和技術(shù)依據(jù)。
[Abstract]:The heat shock transcription factor Hsf) can bind to the heat shock element in the promoter region of the heat shock protein gene and initiate the heat shock reaction directly. Therefore, it has been suggested that there are at least 30 Hsf family members in Zea mays gene transduction pathway under heat stress, of which 4 belong to 18 A 2 subfamilies. On the basis of studying the function of drought resistance and heat resistance, the complete coding sequence of A2 subfamily gene ZmHsf04(Gen Bank was obtained from maize young leaves by homologous cloning technique, which was named as ZmHsf04(Gen Bank accession number: GRMZM2G010871P01). The sequence is 1 074 BP and encodes 357 amino acid residues. The protein structure contains the DNA binding domain of the Hsf family. Complete functional domains such as nuclear localization signal KRKELEDTISKRRRRN, nuclear output signal LQQLGYL) and activated domain LKMFESGVLN) were found. The homology of protein sequence with Sorghum bicolor)SORBIDRAFT_01g021490 was the highest, up to 90%. Under normal growth conditions, ZmHsf04 was expressed in several tissues and organs of maize, and the expression level of ZmHsf04 in young pollen was higher than that in young root control. The expression level of ZmHsf04 was significantly increased under 42 鈩，

本文編號(hào)：1651933