title: The time required for dormancy release in Arabidopsis is determined by DELAY OF GERMINATION1 protein levels in freshly harvested seeds.
abstract: Seed dormancy controls the start of a plant's life cycle by preventing germination of a viable seed in an unfavorable season. Freshly harvested seeds usually show a high level of dormancy, which is gradually released during dry storage (after-ripening). Abscisic acid (ABA) has been identified as an essential factor for the induction of dormancy, whereas gibberellins (GAs) are required for germination. The molecular mechanisms controlling seed dormancy are not well understood. DELAY OF GERMINATION1 (DOG1) was recently identified as a major regulator of dormancy in Arabidopsis thaliana. Here, we show that the DOG1 protein accumulates during seed maturation and remains stable throughout seed storage and imbibition. The levels of DOG1 protein in freshly harvested seeds highly correlate with dormancy. The DOG1 protein becomes modified during after-ripening, and its levels in stored seeds do not correlate with germination potential. Although ABA levels in dog1 mutants are reduced and GA levels enhanced, we show that DOG1 does not regulate dormancy primarily via changes in hormone levels. We propose that DOG1 protein abundance in freshly harvested seeds acts as a timer for seed dormancy release, which functions largely independent from ABA.
authors: Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany. nakabaya@mpipz.mpg.de
authors: Kazumi
authors: K
authors: Nakabayashi
authors: Melanie
authors: M
authors: Bartsch
authors: Yong
authors: Y
authors: Xiang
authors: Emma
authors: E
authors: Miatton
authors: Silke
authors: S
authors: Pellengahr
authors: Ryoichi
authors: R
authors: Yano
authors: Mitsunori
authors: M
authors: Seo
authors: Wim J J
authors: WJ
authors: Soppe
mesh_terms: D000040:Abscisic Acid / Q000032:analysis / Q000378:metabolism*; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D018525:Germination; D005875:Gibberellins / Q000032:analysis / Q000378:metabolism; D009154:Mutation; D057445:Plant Dormancy; D010937:Plant Growth Regulators / Q000032:analysis / Q000378:metabolism*; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D012639:Seeds / Q000166:cytology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction; D013696:Temperature; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D029681:Arabidopsis Proteins; C532384:DOG1 protein, Arabidopsis; D005875:Gibberellins; D010937:Plant Growth Regulators; D012333:RNA, Messenger; D018749:RNA, Plant; D000040:Abscisic Acid