title: Molecular cloning and promoter analysis of the specific salicylic acid biosynthetic pathway gene phenylalanine ammonia-lyase (AaPAL1) from Artemisia annua.
abstract: Phenylalanine ammonia-lyase (PAL) is the key enzyme in the biosynthetic pathway of salicylic acid (SA). In this study, a full-length cDNA of PAL gene (named as AaPAL1) was cloned from Artemisia annua. The gene contains an open reading frame of 2,151 bps encoding 716 amino acids. Comparative and bioinformatics analysis revealed that the polypeptide protein of AaPAL1 was highly homologous to PALs from other plant species. Southern blot analysis revealed that it belonged to a gene family with three members. Quantitative RT-PCR analysis of various tissues of A. annua showed that AaPAL1 transcript levels were highest in the young leaves. A 1160-bp promoter region was also isolated resulting in identification of distinct cis-regulatory elements including W-box, TGACG-motif, and TC-rich repeats. Quantitative RT-PCR indicated that AaPAL1 was upregulated by salinity, drought, wounding, and SA stresses, which were corroborated positively with the identified cis-elements within the promoter region. AaPAL1 was successfully expressed in Escherichia. coli and the enzyme activity of the purified AaPAL1 was approximately 287.2 U/mg. These results substantiated the involvement of AaPAL1 in the phenylalanine pathway.
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Xueqing
authors.initials: X
authors.lastname: Fu
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Hao
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Lida
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Luyao
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Qian
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, Plant Biotechnology Research Center, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
authors.forename: Jingya
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000595:Amino Acid Sequence; D031172:Artemisia annua / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D010650:Phenylalanine Ammonia-Lyase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism* / Q000494:pharmacology; D054712:Salinity; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D012333:RNA, Messenger; D010650:Phenylalanine Ammonia-Lyase; D020156:Salicylic Acid
keywords: Artemisia annua L; phenylalanine ammonia-lyase; quantitative RT-PCR; salicylic acid