A New Lead Chemical for Strigolactone Biosynthesis Inhibitors

Abstract

Several triazole-containing chemicals have previously been shown to act as efficient inhibitors of cytochrome P450 monooxygenases. To discover a strigolactone biosynthesis inhibitor, we screened a chemical library of triazole derivatives to find chemicals that induce tiller bud outgrowth of rice seedlings. We discovered a triazole-type chemical, TIS13 [2,2-dimethyl-7-phenoxy-4-(1H-1,2,4-triazol-1-yl)heptan-3-ol], which induced outgrowth of second tiller buds of wild-type seedlings, as observed for non-treated strigolactone-deficient d10 mutant seedlings. TIS13 treatment reduced strigolactone levels in both roots and root exudates in a concentration-dependent manner. Co-application of GR24, a synthetic strigolactone, with TIS13 canceled the TIS13-induced tiller bud outgrowth. Taken together, these results indicate that TIS13 inhibits strigolactone biosynthesis in rice seedlings. We propose that TIS13 is a new lead compound for the development of specific strigolactone biosynthesis inhibitors.

Molecular mechanism of strigolactone perception by DWARF14

“…Shiokari) was used in this study. Rice plants were grown as described previously 43 with some modifications. Germinated seeds were transferred into hydroponic culture medium 2 that was solidified with 0.6% agar and cultured at 25°C under fluorescent white light with a 16-h light/8-h dark photoperiod for 6 days.…”

Regulation of Strigolactone Biosynthesis by Gibberellin Signaling

“…GA-deficient mutants show increased tiller bud outgrowth and dwarfism (Lo et al, 2008;Ito et al, 2010). To evaluate the effects of SL on GA-deficient rice, we used the GA-deficient mutant Tanginbozu.…”

Effects of strigolactone-biosynthesis inhibitor TIS108 onArabidopsis

“…Although TIS13 inhibits the production of epi-5DS, which is a major SL, in rice, TIS13-treated plants show a severe dwarf phenotype which does not recover following the application of SL; this suggests the possibility that TIS13 inhibits the biosynthesis of other plant hormones such as gibberellin (GA) and/or brassinosteroid (BR). 9 To develop specific SL-biosynthesis inhibitors, a structure-activity relationship study on TIS13 derivatives tiS108 is a triazole-type strigolactone (SL)-biosynthesis inhibitor that reduces the level of 2'-epi-5-deoxystrigol (epi-5DS) in rice. here we report the effects of tiS108 on Arabidopsis.…”

“…Previously, we chose triazole derivatives as these have been shown to act as efficient inhibitors of P450 monooxygenase and reported two SL-biosynthesis inhibitors, 2,2-dimethyl-7-phenoxy-4-(1H-1,2,4-triazol-1-yl)heptan-3-ol (TIS13) 9 and 6-phenoxy-1-phenyl-2-(1H-1,2,4-triazol-1-yl) hexan-1-one (TIS108) 10 ( Fig. 1A).…”