title: Development of a salicylic acid inducible minimal sub-genomic transcript promoter from Figwort mosaic virus with enhanced root- and leaf-activity using TGACG motif rearrangement.
abstract: In Figwort mosaic virus sub-genomic transcript promoter (F-Sgt), function of the TGACG-regulatory motif, was investigated in the background of artificially designed promoter sequences. The 131bp (FS, -100 to +31) long F-Sgt promoter sequence containing one TGACG motif [FS-(TGACG)] was engineered to generate a set of three modified promoter constructs: [FS-(TGACG)(2), containing one additional TGACG motif at 7 nucleotides upstream of the original one], [FS-(TGACG)(3), containing two additional TGACG motifs at 7 nucleotides upstream and two nucleotides downstream of the original one] and [FS-(TGCTG)(mu), having a mutated TGACG motif]. EMSA and foot-printing analysis confirmed binding of tobacco nuclear factors with modified TGACG motif/s. The transcription-activation of the GUS gene by the TGACG motif/s in above promoter constructs was examined in transgenic tobacco and Arabidopsis plants and observed that the transcription activation was affected by the spacing/s and number/s of the TGACG motif/s. The FS-(TGACG)(2) promoter showed strongest root-activity compared to other modified and CaMV35S promoters. Also under salicylic acid (SA) stress, the leaf-activity of the said promoter was further enhanced. All above findings were confirmed by real-time and semi-qRT PCR analysis. Taken together, these results clearly demonstrated that the TGACG motif plays an important role in inducing the root-specific expression of the F-Sgt promoter. This study advocates the importance of genetic manipulation of functional cis-motif for amending the tissue specificity of a plant promoter. SA inducible FS-(TGACG)(2) promoter with enhanced activity could be a useful candidate promoter for developing plants with enhanced crop productivity.
authors.affiliation: Department of Gene Function and Regulation, Institute of Life Sciences, Government of India, Chandrasekherpur, Orissa, India. dpkbiotech@gmail.com
authors.forename: Deepak
authors.initials: D
authors.lastname: Kumar
authors.forename: Sunita
authors.initials: S
authors.lastname: Patro
authors.forename: Jayasish
authors.initials: J
authors.lastname: Ghosh
authors.forename: Abhimanyu
authors.initials: A
authors.lastname: Das
authors.forename: Indu B
authors.initials: IB
authors.lastname: Maiti
authors.forename: Nrisingha
authors.initials: N
authors.lastname: Dey
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D017796:Caulimovirus / Q000235:genetics*; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D059372:Nucleotide Motifs / Q000235:genetics*; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000187:drug effects*; D020156:Salicylic Acid / Q000494:pharmacology*; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects*
chemical_list: D000890:Anti-Infective Agents; D005966:Glucuronidase; D020156:Salicylic Acid