The J-protein AtDjB1 is required for mitochondrial complex I activity and regulates growth and development through ROS-mediated auxin signalling.
AtDjB1 is a mitochondria-located J-protein in Arabidopsis thaliana It is involved in the regulation of plant growth and development; however, the exact mechanisms remain to be determined. We performed comparison analyses of phenotypes, auxin signalling, redox status, mitochondrial structure and function using wild-type plants, AtDjB1 mutants, rescued AtDjB1 mutants by AtDjB1 or YUCCA2 (an auxin synthesis gene), and AtDjB1 overexpression plants. AtDjB1 mutants (atj1-1 or atj1-4) exhibited inhibition of growth and development and reductions in the level of IAA and the expression of YUCCA genes compared to wild-type plants. The introduction of AtDjB1 or YUCCA2 into atj1-1 largely rescued phenotypic defects and the IAA level, indicating that AtDjB1 probably regulates growth and development via auxin. Furthermore, atj1-1 plants displayed a significant reduction in amount/activity of mitochondrial complex I compared to wild-type plants; this resulted in the accumulation of reactive oxygen species (ROS). Moreover, exogenous H2O2 markedly inhibited the expression of YUCCA genes in wild-type plants. In contrast, the reducing agent ascorbate increased the expression of YUCCA genes and IAA level in atj1-1 plants, indicating that the low auxin level observed in atj1-1 was probably due to the high oxidation status. Overall, the data presented here suggest that AtDjB1 is required for mitochondrial complex I activity and regulates growth and development through ROS-mediated auxin signalling in Arabidopsis.
Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang 050024, China.
Ning
N
Jia
Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang 050024, China.
Ting-Ting
TT
Lv
Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang 050024, China.
Mi-Xin
MX
Li
Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang 050024, China.
Shan-Shan
SS
Wei
Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang 050024, China.
Yan-Yi
YY
Li
Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang 050024, China.
Chun-Lan
CL
Zhao
Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, College of Life Science, Hebei Normal University, Shijiazhuang 050024, China libing@mail.hebtu.edu.cn.
Bing
B
Li
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D042967:Electron Transport Complex I / Q000378:metabolism*; D050956:HSP40 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism*; D006899:Mixed Function Oxygenases; D009245:NADH Dehydrogenase; D010937:Plant Growth Regulators / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction
C494632:ATJ1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D050956:HSP40 Heat-Shock Proteins; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D017382:Reactive Oxygen Species; D006899:Mixed Function Oxygenases; C000608861:YUCCA2 protein, Arabidopsis; D009245:NADH Dehydrogenase; D042967:Electron Transport Complex I
Arabidopsis thaiana; AtDjB1; ROS.; auxin; complex I; growth and development; reactive oxygen species