title: Knockout of AtDjB1, a J-domain protein from Arabidopsis thaliana, alters plant responses to osmotic stress and abscisic acid.
abstract: AtDjB1 is a member of the Arabidopsis thaliana J-protein family. AtDjB1 is targeted to the mitochondria and plays a crucial role in A. thaliana heat and oxidative stress resistance. Herein, the role of AtDjB1 in adapting to saline and drought stress was studied in A. thaliana. AtDjB1 expression was induced through salinity, dehydration and abscisic acid (ABA) in young seedlings. Reverse genetic analyses indicate that AtDjB1 is a negative regulator in plant osmotic stress tolerance. Further, AtDjB1 knockout mutant plants (atj1-1) exhibited greater ABA sensitivity compared with the wild-type (WT) plants and the mutant lines with a rescued AtDjB1 gene. AtDjB1 gene knockout also altered the expression of several ABA-responsive genes, which suggests that AtDjB1 is involved in osmotic stress tolerance through its effects on ABA signaling pathways. Moreover, atj1-1 plants exhibited higher glucose levels and greater glucose sensitivity in the post-germination development stage. Applying glucose promoted an ABA response in seedlings, and the promotion was more evident in atj1-1 than WT seedlings. Taken together, higher glucose levels in atj1-1 plants are likely responsible for the greater ABA sensitivity and increased osmotic stress tolerance.
authors: Hebei Key Laboratory of Molecular and Cellular Biology, College of Life Science, Hebei Normal University, Shijiazhuang, 050024, PR China.
authors: Xingxing
authors: X
authors: Wang
authors: Ning
authors: N
authors: Jia
authors: Chunlan
authors: C
authors: Zhao
authors: Yulu
authors: Y
authors: Fang
authors: Tingting
authors: T
authors: Lv
authors: Wei
authors: W
authors: Zhou
authors: Yongzhen
authors: Y
authors: Sun
authors: Bing
authors: B
authors: Li
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018548:Cotyledon / Q000187:drug effects / Q000254:growth & development; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D055786:Gene Knockout Techniques; D017343:Genes, Plant; D018525:Germination / Q000187:drug effects; D005947:Glucose / Q000378:metabolism; D050956:HSP40 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D008353:Mannitol / Q000494:pharmacology; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D009997:Osmotic Pressure / Q000187:drug effects*; D017434:Protein Structure, Tertiary; D054712:Salinity; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: C494632:ATJ1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D050956:HSP40 Heat-Shock Proteins; D008353:Mannitol; D012965:Sodium Chloride; D000040:Abscisic Acid; D005947:Glucose