Dehydroabietinal, an abietane diterpenoid, activates the autonomous pathway to impact flowering time and defense in Arabidopsis thaliana
Z. CHOWDHURY (1) (1) University of North Texas, U.S.A.

Plants are the major source of abietane diterpenes, which are tricyclic diterpenoid natural products of medicinal and industrial values.  However, the function of these diterpenes in plants is poorly understood. Dehydroabietinal (DA) is an abietane diterpene that is a potent inducer of plant defense. Experiments with a DA biosynthesis mutant confirm an important role for DA in long-distance signaling associated with systemic acquired resistance (SAR) in Arabidopsis thaliana. Here, we show DA also plays vital role in the development of angiosperms by controlling the timing of transition from vegetative to reproductive phase. DA is required for the activation of the autonomous pathway. DA activates expression of the autonomous pathway genes FLOWERING LOCUS D (FLD), RELATIVE OF EARLY FLOWERING 6 (REF6) and FVE, which are involved in chromatin remodeling that represses expression of FLOWERING LOCUS C (FLC), thereby stimulating FLOWERING LOCUS T expression to promote flowering. FLD, REF6 and FVE are also required for the activation of SAR. The involvement of the autonomous pathway in SAR is also supported by our studies with the DA-insensitive mutants’ ida2/7 and ida37, which are defective in the expression of FLD and exhibit a SAR-deficient and delayed flowering phenotype.

Abstract Number: P16-445
Session Type: Poster