Arabidopsis mtHSC70-1 plays important roles in the establishment of COX-dependent respiration and redox homeostasis. (6th August 2019)

• Record Type: Journal Article
• Authors: Wei, Shan-Shan; Niu, Wei-Tao; Zhai, Xiao-Ting; Liang, Wei-Qian; Xu, Meng; Fan, Xiao; Lv, Ting-Ting; Xu, Wen-Yan; Bai, Jiao-Teng; Jia, Ning; Li, Bing
• Editors: Foyer, Christine
• Is Part Of: Journal of experimental botany. Volume 70:Number 20(2019)
• Page Start: 5575
• Page End: 5590
• Publication Date: 2019-08-06
• Subjects: Arabidopsis -- cytochrome c oxidase -- growth and development -- mtHSC70-1 -- reactive oxygen species -- respiratory complex IV; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erz357
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: The 70 kDa heat shock proteins function as molecular chaperones and are involved in diverse cellular processes. However, the functions of the plant mitochondrial HSP70s (mtHSC70s) remain unclear. Severe growth defects were observed in the Arabidopsis thaliana mtHSC70-1 knockout lines, mthsc70-1a and mthsc70-1b . Conversely, the introduction of the mtHSC70-1 gene into the mthsc70-1a background fully reversed the phenotypes, indicating that mtHSC70-1 is essential for plant growth. The loss of mtHSC70-1 functions resulted in abnormal mitochondria and alterations to respiration because of an inhibition of the cytochrome c oxidase (COX) pathway and the activation of the alternative respiratory pathway. Defects in COX assembly were observed in the mtHSC70-1 knockout lines, leading to decreased COX activity. The mtHSC70-1 knockout plants have increased levels of reactive oxygen species (ROS). The introduction of the Mn-superoxide dismutase 1 ( MSD1 ) or the catalase 1 ( CAT1 ) gene into the mthsc70-1a plants decreased ROS levels, reduced the expression of alternative oxidase, and partially rescued growth. Taken together, our data suggest that mtHSC70-1 plays important roles in the establishment of COX-dependent respiration. Abstract : mtHSC70-1 is essential for plant growth, and plays crucial roles in regulating respiration and redox homeostasis through affecting the abundance of the cytochrome c oxidase.