本文選題：抗凍蛋白(AFPs) + PrdA啟動(dòng)子　； 參考：《農(nóng)業(yè)生物技術(shù)學(xué)報(bào)》2017年08期

【摘要】：抗凍蛋白(antifreeze proteins,AFPs)是耐寒生物為適應(yīng)冷環(huán)境而產(chǎn)生的特殊小分子蛋白質(zhì),具有降低冰點(diǎn)、抑制重結(jié)晶的作用。本實(shí)驗(yàn)研究了在環(huán)境誘導(dǎo)型啟動(dòng)子(Prd29A(responsive to desiccation29A))和組成型啟動(dòng)子(花椰菜花葉病毒35S(Cauliflower mosaic virus 35S,Ca MV 35S))驅(qū)動(dòng)下胡蘿卜(Daucus carota)AFP在煙草(Nicotiana tabacum)中的表達(dá)。結(jié)果表明,Dc AFP基因已整合到煙草基因組中且可以穩(wěn)定遺傳,T1轉(zhuǎn)基因煙草花序發(fā)育不良,蒴果容易從果柄基部脫落,極少數(shù)果實(shí)能夠正常發(fā)育;4℃低溫馴化10 d,-1℃處理24 h,室溫恢復(fù)生長(zhǎng)1周,T1代轉(zhuǎn)Prd29A:Dc AFP基因煙草存活率比轉(zhuǎn)Ca MV35S:Dc AFP基因煙草高34.6%,比野生型煙草高61.1%,且長(zhǎng)勢(shì)良好,而野生型煙草大多數(shù)枯萎死亡;低溫脅迫處理導(dǎo)致所有煙草葉綠素?zé)晒鈪?shù)Fv/Fm均有所降低,但25℃恢復(fù)生長(zhǎng)后,轉(zhuǎn)Prd29A:Dc AFP基因煙草Fv/Fm接近正常水平,而轉(zhuǎn)CaMV35S:DcAFP基因煙草Fv/Fm僅比野生型略高;與野生型對(duì)比,兩種不同啟動(dòng)子驅(qū)動(dòng)的轉(zhuǎn)Dc AFP基因煙草在4℃低溫馴化(0~15 d)期間積累了較多的脯氨酸、可溶性蛋白及可溶性糖等滲透調(diào)節(jié)物質(zhì),抗氧化酶(超氧化物歧化酶(superoxide dismutase,SOD)和過氧化物酶(peroxidase,POD))酶活有所提高,同工酶譜帶增多;特別是轉(zhuǎn)Prd29A:DcAFP基因煙草比轉(zhuǎn)CaMV35S:DcAFP基因煙草中脯氨酸含量、可溶性糖含量、可溶性蛋白含量、SOD酶活酶活及POD酶活分別增加45.1%、12.1%、20%、19.7%、8.6%,而且轉(zhuǎn)入Prd29A啟動(dòng)子驅(qū)動(dòng)的DcAFP基因可以更有效的提高轉(zhuǎn)基因煙草的抗寒性,并且其對(duì)轉(zhuǎn)基因煙草生長(zhǎng)發(fā)育影響相對(duì)較小。研究結(jié)果對(duì)于抗凍轉(zhuǎn)基因植物的培育具有重要參考價(jià)值。
[Abstract]:Antifreeze proteins (antifreeze proteinsAFPs) are special small molecular proteins produced by cold-tolerant organisms to adapt to cold environment, which can reduce freezing point and inhibit recrystallization. In this study, the expression of Daucus carota AFP in tobacco (Nicotiana tabacum) induced by environmental inducible promoter (Prd29A (responsive to desiccation29A) and constitutive promoter (Cauliflower mosaic virus 35s (Cauliflower mosaic virus 35S) was studied. The results showed that the DcAFP gene had been integrated into the tobacco genome and could be stably inherited as the inflorescence of T 1 transgenic tobacco inflorescence was poor, and the capsule could easily be removed from the base of the stalk. A few fruits could develop normally at 4 鈩，

本文編號(hào)：2095393