Cloning and Characterization of a Gene Encoding Rac/Rop-Like Monomeric Guanosine 5′-Triphosphate-Binding Protein from Scoparia dulcis

• Published in: Biological & Pharmaceutical Bulletin 2009/06/01, Vol.32(6), pp.1122-1125
• Main Authors: Mitamura, Toshiaki, Shite, Masato, Yamamura, Yoshimi, Kurosaki, Fumiya
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Blotting, Southern; Cloning, Molecular; ethylene; Gene Expression; Genes, Plant; methyl jasmonate; Molecular Sequence Data; Phylogeny; Plant Proteins - genetics; rac GTP-Binding Proteins - genetics; Rac/Rop guanosine 5′-triphosphate-binding protein; Reverse Transcriptase Polymerase Chain Reaction; Scoparia - drug effects; Scoparia - genetics; Scoparia - metabolism; Scoparia dulcis; Sequence Alignment; signal transduction
• ISSN: 0918-6158; 1347-5215
• DOI: 10.1248/bpb.32.1122

A cDNA clone, designated Sd-racrop (969 bp), was isolated from seedlings of Scoparia dulcis. This gene contains an open reading frame encoding the protein of 197 amino acid residues with high homology to Rac/Rop small guanosine 5′-triphosphate-binding proteins from various plant sources. In Southern hybridization analysis, the restriction digests prepared from genomic DNA of S. dulcis showed a main signal together with a few weakly hybridized bands. The transcriptional level of Sd-racrop showed a transient decrease by exposure of the leaf tissues of S. dulcis to the ethylene-generating reagent 2-chloroethylphosphonic acid. However, an appreciable increase in gene expression was reproducibly observed upon treatment of the plant with methyl jasmonate. These results suggest that the Sd-racrop product plays roles in ethylene- and methyl jasmonate-induced responses of S. dulcis accompanying the change in the transcriptional level, however, the cellular events mediated by this protein toward these external stimuli would be regulated by various mechanisms.