Department of Biology
Proanthocyanidins inhibit seed germination by maintaining a high level of abscisic acid in arabidopsis thaliana
Proanthocyanidins (PAs) are the main products of the flavonoid biosynthetic pathway in seeds, but their biological function during seed germination is still unclear. We observed that seed germination is delayed with the increase of exogenous PA concentration in Arabidopsis. A similar inhibitory effect occurred in peeled Brassica napus seeds, which was observed by measuring radicle elongation. Using abscisic acid (ABA), a biosynthetic and metabolic inhibitor, and gene expression analysis by real-time polymerase chain reaction, we found that the inhibitory effect of PAs on seed germination is due to their promotion of ABA via de novo biogenesis, rather than by any inhibition of its degradation. Consistent with the relationship between PA content and ABA accumulation in seeds, PA-deficient mutants maintain a lower level of ABA compared with wild-types during germination. Our data suggest that PA distribution in the seed coat can act as a doorkeeper to seed germination. PA regulation of seed germination is mediated by the ABA signaling pathway. © 2012 Institute of Botany, Chinese Academy of Sciences.
Abscisic acid, Arabidopsis, Brassica napus, Proanthocyanidins, Seed germination
Source Publication Title
Journal of Integrative Plant Biology
Jia, Liguo, Qiuyu Wu, Nenghui Ye, Rui Liu, Lu Shi, Weifeng Xu, Hui Zhi, A.N.M. Rubaiyath Bin Rahman, Yiji Xia, and Jianhua Zhang. "Proanthocyanidins inhibit seed germination by maintaining a high level of abscisic acid in arabidopsis thaliana." Journal of Integrative Plant Biology 54.9 (2012): 663-673.