title: A cis-element responsible for cGMP in the promoter of the soybean chalcone synthase gene.
abstract: The cyclic nucleotides cGMP and cAMP have been reported to play key roles in the regulation of plant processes and responses. We have previously reported that several genes encoding flavonoid biosynthetic enzymes, including chalcone synthase (CHS) in soybean (Glycine max L.), were induced by cGMP but not cAMP. The soybean genome contains nine CHS gene copies (GmCHS1-9). We investigated the responsiveness of several GmCHS genes to cGMP, cAMP, NO, and white light. Quantitative RT-PCR analysis showed that the transcript levels of GmCHS7 and GmCHS8 were increased by 3.6- and 3.8-fold, respectively, with cGMP whereas the transcript levels of GmCHS2 remained constant. Although cAMP had no effect on the transcript levels of the three genes, NO had an activation effect on all three. White light activated the three genes in a transient manner, with GmCHS2, GmCHS7, and GmCHS8 transcript levels increasing 3-fold after 3 h and decreasing to basal levels after 9 h. The GmCHS8 promoter contains several important cis-elements, including the G-box and H-box forming the Unit-I-like sequence and the MYB binding sequence, a target of the GmMYB176 transcription factor regulating the expression of GmCHS8. A transient gene expression assay revealed the activation of the Unit-I-like sequence, but not of the MYB binding sequence, by cGMP. The combination of G-box and H-box was necessary for cGMP responsiveness. Taken together, these results suggest that the Unit-I-like sequence in the promoters of GmCHS7 and GmCHS8 is a cGMP responsive cis-element in these genes and that NO exerts its effect via cis-elements other than the Unit-I-like sequence.
authors.affiliation: Laboratory of Biochemistry, Graduate School of Agricultural Science, Kobe University, Rokkodai-cho 1-1, Nada-ku, Kobe 657-8501, Japan.
authors.forename: Hamad
authors.initials: H
authors.lastname: Abu Zahra
authors.affiliation: Laboratory of Biochemistry, Graduate School of Agricultural Science, Kobe University, Rokkodai-cho 1-1, Nada-ku, Kobe 657-8501, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Kuwamoto
authors.affiliation: Laboratory of Biochemistry, Graduate School of Agricultural Science, Kobe University, Rokkodai-cho 1-1, Nada-ku, Kobe 657-8501, Japan.
authors.forename: Tomohide
authors.initials: T
authors.lastname: Uno
authors.affiliation: Laboratory of Biochemistry, Graduate School of Agricultural Science, Kobe University, Rokkodai-cho 1-1, Nada-ku, Kobe 657-8501, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Kanamaru
authors.affiliation: Laboratory of Biochemistry, Graduate School of Agricultural Science, Kobe University, Rokkodai-cho 1-1, Nada-ku, Kobe 657-8501, Japan. Electronic address: yamagata@kobe-u.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamagata
mesh_terms: D000217:Acyltransferases / Q000235:genetics*; D001483:Base Sequence; D006152:Cyclic GMP / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D009569:Nitric Oxide / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013025:Glycine max / Q000201:enzymology / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D009569:Nitric Oxide; D000217:Acyltransferases; C020141:flavanone synthetase; D006152:Cyclic GMP
keywords: 2-hydroxyisoflavanone dehydratase; 2-hydroxyisoflavanone synthase; 3′,5′-cyclic guanosine monophosphate; 4-coumarate:CoA ligase; 4CL; ANS; C4H; CHI; CHR; CHS; Chalcone synthase; Flavonoid biosynthesis; Glycine max; HIDH; IFGT; IFR; IFS; NO; Nitric oxide; PAL; Parsley crispum CHS; PcCHS; UDP-glucose:isoflavone 7-O-glucosyltransferase; anthocyanidin synthase; chalcone isomerase; chalcone reductase; chalcone synthase; cinnamate 4-hydroxylase; cis-element; isoflavone reductase; nitric oxide; phenylalanine ammonia lyase