|J Integr Plant Biol, 54 (9): 663-673, Research Article|
|Proanthocyanidins Inhibit Seed Germination by Maintaining High Level of Abscisic Acid in Arabidopsis thaliana|
|1Department of Biology, Hong Kong Baptist University, Hong Kong, China
2School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
*Corresponding author Tel: (852) 39436288; Fax: (852) 26036382; E-mail: firstname.lastname@example.org
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.
Jia L, Wu Q, Ye N, Liu R, Shi L, Xu W, Zhi H, Rahman ANMRB, Xia Y, Zhang J (2012) Proanthocyanidins inhibit seed germination by maintaining a high level of abscisic acid in Arabidopsis thaliana. J. Integr. Plant Biol. 54(9), 663–673.
|Received: 16 January 2012 Published: 05 July 2012|
|© 2012 Institute of Botany, Chinese Academy of Sciences|