Sugar signaling is involved in histone deacetylase-mediated repression of embryonic characteristics after germination

Abstract

Sugars are important regulators of germination and seedling development, and sugar signaling is thought to be involved in the repression of embryonic characteristics after germination. In contrast, chromatin remodeling induced by histone modification plays an important role in the control of plant development. We found that HDA6 and HDA19 redundantly repress embryo-specific gene expression during germination in Arabidopsis. We analyzed the effects of sucrose-containing or sucrose-free medium on post-germination growth arrest in an HDA6/19 double repression line (HDA6/19:RNAi). Although HDA6/19:RNAi seeds showed post-germination growth arrest when grown in sucrose-containing medium, sucrose-free medium relieved growth arrest, indicating the suppression of embryo-specific genes. Thus, sugar signaling may prevent the HDAC-mediated repression of embryonic characteristics after germination. Based on expression analyses of VSP2 in HDA6/19:RNAi seedlings, the repression of HDA6 and HDA19 may not affect sugar signaling. During germination, HDA6 and HDA19 repress embryonic properties via regulation of embryo-specific transcription factors. Sugar signaling may also contribute to this repression of embryonic properties.