三角褐指藻八氢番茄红素脱氢酶1-2基因启动子克隆和表达分析  

Cloning and Expression Analysis of the Promoters of Phytoene Desaturase 1-2 Gene in Phaeodactylum tricornutum

作　　者：吕娇 龚一富[1] 章丽[1] 吴欣 王何瑜[2] LV Jiao;GONG Yi-Fu;ZHANG Li;WU Xin;WANG He-Yu(Key Laboratory of Marine Biotechnology of Zhejiang Province,School of Marine Sciences;College of Food and Pharmaceutical Sciences,Experimental Teaching Center,Ningbo University,Ningbo 315832,Zhejiang,China)

机构地区：[1]宁波大学海洋学院,浙江省海洋生物工程重点实验室,浙江宁波315832 [2]宁波大学食品与药学学院,实验教学中心,浙江宁波315832

出　　处：《中国生物化学与分子生物学报》2023年第6期870-879,共10页Chinese Journal of Biochemistry and Molecular Biology

基　　金：宁波市社发重大项目(No.2017C510002);宁波大学横向项目(No.HX2022000115)资助。

摘　　要：八氢番茄红素脱氢酶(phytoene desaturase,PDS)是类胡萝卜素合成的关键酶,在光合生物的类胡萝卜素代谢调控中发挥了重要的作用。本研究根据三角褐指藻基因组数据库,克隆三角褐指藻PDS1和PDS2基因启动子序列,采用启动子缺失技术研究启动子活性,利用Plant CARE预测三角褐指藻PDS1和PDS2启动子顺式作用元件,采用qRT-PCR技术检测三角褐指藻PDS1和PDS2基因在不同胁迫下的相对表达量。结果表明,三角褐指藻PDS1和PDS2基因启动子全长分别为2000 bp和920 bp,不同长度的5′端缺失后启动子均能驱动绿色荧光蛋白表达,具有较强启动子活性。Plant CARE分析结果表明,三角褐指藻PDS1和PDS2基因启动子中均含有与光照和植物激素响应有关的顺式作用元件。光照和植物激素胁迫处理结果表明,三角褐指藻PDS1基因受光合诱导因子(photosynthetic induction factor,PIF)的诱导表达,但在其他因子处理下表达均显著下降(P<0.05)或无显著性差异。三角褐指藻PDS2基因在PIF、红光、茉莉酸甲酯、乙酰水杨酸和脱落酸胁迫下均表达上调(P<0.05),在光合作用抑制剂二氯苯基二甲脲(dichlorophenyl dimethylurea,DCMU)、黄光和蓝光胁迫下显著下调(P<0.05)。三角褐指藻PDS2基因在不同处理下的基因表达和岩藻黄素含量呈显著的正相关关系(r=0.8551,P<0.01),说明PDS2基因可能是三角褐指藻岩藻黄素合成的关键基因。本研究揭示了三角褐指藻的PDS基因参与光系统和植物激素胁迫应答的新功能,为进一步研究岩藻黄素调控机制提供了一定的理论基础。Phytoene desaturase(PDS)is a key enzyme in carotenoid synthesis and plays an important role in the regulation of carotenoid metabolism in photosynthetic organisms.In this study,the promoter sequences of PDS1 and PDS2 genes were cloned from the genome database of Phaeodactylum tricornutum,and the promoter activity was investigated by promoter deletion technique.The relative expression of PDS1 and PDS2 genes in P.tricornutum under different stresses was measured by qRT-PCR.The results showed that the promoters of PDS1 and PDS2 genes were 2000 bp and 920 bp in length respectively,and the promoters were able to drive the expression of green fluorescent protein after deletion of the 5′end of different lengths,which had strong promoter activity.The PDS1 and PDS2 promoters both contain cisacting elements related to light and phytohormone response.The results of light and phytohormone stress treatments showed that the PDS1 gene was induced by PIF,but that expression was significantly reduced(P<0.05)or not significantly different in response to other factors.The PDS2 gene was up-regulated by photosynthetic induction factor(PIF),red light,methyl jasmonate,acetylsalicylic acid and abscisic acid stress(P<0.05)and significantly down-regulated by dichlorophenyl dimethylurea(DCMU),yellow light and blue light stress(P<0.05).A significant positive correlation was found between PDS2 gene expression and fucoxanthin content in P.tricornutum under different treatments(r=0.8551,P<0.01),suggesting that PDS2 gene may be the key gene for fucoxanthin biosynthesis in P.tricornutum.The present study reveals a new function of the PDS gene of P.tricornutum in the photosystem and phytohormone stress response,which provides a theoretical basis for further studies on the mechanism of fucoxanthin regulation in P.tricornutum.

关 键 词：八氢番茄红素脱氢酶 启动子 岩藻黄素 三角褐指藻 

分 类 号：Q7[生物学—分子生物学]