title: Involvement of GIGANTEA gene in the regulation of the cold stress response in Arabidopsis.
abstract: The Arabidopsis GIGANTEA (GI) gene has been shown to regulate several developmental processes, including photoperiod-mediated flowering, phytochrome B signaling, circadian clock, and carbohydrate metabolism. However, little is known about the role of GI gene in mediating the cold stress response. Here, we show that GI gene is involved in mediating the cold stress response. GI gene was induced by cold stress, but not by salt, mannitol, and abscisic acid. Moreover, gi-3 plants showed an increased sensitivity to freezing stress. However, no significant differences were detected in the transcript levels of CBF genes CBF1, CBF2, and CBF3 as well as their targeted genes RD29A, COR15A, KIN1, and KIN2 between wild-type and gi-3 plants in response to cold stress. These results suggest that GI gene positively regulates freezing tolerance via a CBF-independent pathway. In addition, intermittent cold treatments had a greater effect on flowering time in gi-3 plants than that in wild-type plants, suggesting that there may be a link between flowering time and cold stress response through GI in Arabidopsis.
authors.affiliation: School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China. phdcsq@163.com
authors.forename: Shuqing
authors.initials: S
authors.lastname: Cao
authors.forename: Ming
authors.initials: M
authors.lastname: Ye
authors.forename: Shaotong
authors.initials: S
authors.lastname: Jiang
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000064:Acclimatization / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003080:Cold Temperature / Q000009:adverse effects*; D035264:Flowers / Q000502:physiology; D005615:Freezing; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D008353:Mannitol / Q000494:pharmacology; D009154:Mutation / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000033:anatomy & histology; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D029681:Arabidopsis Proteins; C121183:GI protein, Arabidopsis; D012333:RNA, Messenger; D008353:Mannitol; D012965:Sodium Chloride; D000040:Abscisic Acid