The chromatin protein EARLY BOLTING IN SHORT DAYS regulates seed dormancy in Arabidopsis

Seed dormancy represents the transient inability of an intact and viable seed to germinate, even under favorable conditions, and is an important trait for plant adaptation and crop yield. This period of seed latency has a profound effect on plant fitness as it determines the diversity of habitats where plants can be established, and contributes decisively to ensure that germination takes place at the right time.

In this work we reveal that the plant-specific chromatin factor EARLY BOLTING IN SHORT DAYS (EBS) has a prominent role in the control of seed dormancy in Arabidopsis. We demonstrate that the EBS gene is necessary for the repression of germination during seed dormancy and that the EBS homologue SHORT LIFE (SHL) is redundant with EBS in the regulation of this process. Transcriptomic analysis of ebs mutant seeds showed that the expression of various genes involved in seed dormancy and germination regulation is controlled by EBS. Among these genes, the AGAMOUS-LIKE67 (AGL67) locus encodes a transcription factor proposed to have a key role in modulating the balance between seed dormancy and germination, and functions in the same pathway as EBS to prevent growth reactivation in the dormant seed. Furthermore, EBS acts independently of other chromatin genes known to control dormancy. Altogether, these observations emphasize that the orchestrated action of various chromatin remodeling processes is essential for the transcriptional regulation of master genes of seed dormancy.