A Chemical Genetics Strategy that Identifies Small Molecules which Induce the Triple Response in Arabidopsis

• Published in: Molecules (Basel, Switzerland) Vol. 22; no. 12; p. 2270
• Main Authors: Oh, Keimei, Hoshi, Tomoki, Tomio, Sumiya, Ueda, Kenji, Hara, Kojiro
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 19-12-2017; MDPI
• Subjects: Arabidopsis; Arabidopsis - drug effects; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Biological activity; Biosynthesis; Correlation analysis; Data processing; Ethylene; Gene expression; Gene Expression Regulation, Plant; Genes; Genes, Plant; Genetics; Germination - drug effects; plant growth regulator; Plant Growth Regulators - pharmacology; Polymerase chain reaction; pyrazole derivatives; Seedlings; Seedlings - drug effects; Seedlings - growth & development; Seedlings - metabolism; Substitution reactions; sulfonamide derivatives; Sulfonamides - pharmacology; Transcriptional Activation; Up-Regulation; sulfonamide derivatives; plant growth regulator; ethylene; pyrazole derivatives
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules22122270

To explore small molecules with ethylene-like biological activity, we conducted a triple response-based assay system for chemical library screening. Among 9600 compounds, we found
-[(1,3,5-trimethyl-1
-pyrazol-4-yl)methyl]-
-methyl-2-naphthalenesulfonamide (
) displayed promising biological activity on inducing a triple response in
seedlings. Chemical synthesis and structure-activity relationship (SAR) analysis of
analogues with different substitution patterns on the phenyl ring structure of the sulfonamide group indicated that 3,4-dichloro-
-methyl-
-(1,3,5-trimethyl-1
-pyrazol-4-yl-methyl) benzenesulfonamide (
) exhibits the most potent biological activity. To determine the mechanism of action, we conducted RNA sequencing (RNA-Seq) analysis of the effect of
and 1-aminocyclopropane-1-carboxylate (ACC), the precursor of ethylene biosynthesis, following the quantitative real-time polymerase chain reaction (RT-PCR) confirmation. Data obtained from RNA-Seq analysis indicated that
and ACC significantly induced the expression of 39 and 48 genes, respectively (above 20 fold of control), among which five genes are up-regulated by
as well as by ACC. We also found 67 and 32 genes that are significantly down-regulated, respectively, among which seven genes are in common. For quantitative RT-PCR analysis. 12 up-regulated genes were selected from the data obtained from RNA-Seq analysis. We found a good correlation of quantitative RT-PCR analysis and RNA-Seq analysis. Based on these results, we conclude that the action mechanism of
on inducing triple response in
is different from that of ACC.