title: The bean PvSR2 gene produces two transcripts by alternative promoter usage.
abstract: The bean (Phaseolus vulgaris) stress-related gene number 2 (PvSR2) is heavy metal-inducible. Here, the intron of PvSR2 (I-PvSR) within the coding sequence was isolated and characterized. I-PvSR exhibited a weak and constitutive promoter activity and enhanced the PvSR2 promoter activity in transiently transformed tobacco protoplasts. The transcription start site of I-PvSR promoter was mapped 72 bp upstream of the 3'-splice site. The shorter PvSR2 transcript (768nt) in bean is generated from this intronic promoter and lacks the last 56 bases of 3'-end sequence of longer PvSR2 transcript (829nt) by utilizing an alternative polyadenylation site. Quantitative competitive PCR analysis further revealed that two transcripts were differently accumulated in response to Hg(2+)-exposure and the longer transcript was more abundant than the shorter one. These results demonstrate an additional non-metal inducible transcription of PvSR2 via alternative intronic promoter usage and provide new insights into expression mechanism of metal inducible gene.
authors.affiliation: Department of Biology, Graduate University of Chinese Academy of Sciences, Yuquan Road 19, Beijing 100049, PR China.
authors.forename: Xiao-Ting
authors.initials: XT
authors.lastname: Qi
authors.forename: Yu-Xiu
authors.initials: YX
authors.lastname: Zhang
authors.forename: Tuan-Yao
authors.initials: TY
authors.lastname: Chai
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D001483:Base Sequence; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000235:genetics*; D007438:Introns; D008627:Mercuric Chloride / Q000494:pharmacology; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D027805:Phaseolus / Q000187:drug effects / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified; D011061:Poly A; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms; D011523:Protoplasts / Q000166:cytology / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014026:Nicotiana / Q000166:cytology / Q000235:genetics; D024363:Transcription Initiation Site; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D006360:Heat-Shock Proteins; D010940:Plant Proteins; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; D011061:Poly A; D008627:Mercuric Chloride; D005966:Glucuronidase