Location: Plant Gene Expression CenterTitle: The plastid-localized AtFtsHi3 pseudo-protease of Arabidopsis thaliana has an impact on plant growth and drought tolerance
|MISHRA, LAXMI - University Of Umea|
|MISHRA, SANATKUMAR - University Of Umea|
|FUNK, CHRISTIANE - University Of California|
Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/28/2021
Publication Date: 6/23/2021
Citation: Mishra, L., Mishra, S., Caddell, D.F., Coleman-Derr, D.A., Funk, C. 2021. The plastid-localized AtFtsHi3 pseudo-protease of Arabidopsis thaliana has an impact on plant growth and drought tolerance. Frontiers in Plant Science. 12:694727. https://doi.org/10.3389/fpls.2021.694727.
Interpretive Summary: Drought is an environmental stress that can negatively impact plant productivity and crop yields. Several classes of chloroplast proteases are involved in the acclimation of plants to drought. The chloroplast serves as the compartment for photosynthesis and houses many vital metabolic pathways crucial for various aspects of plant growth and development. Although the molecular mechanisms remain unclear our findings suggest, ftshi3-1(kd) displayed a drought-tolerant phenotype both in young and adult plants in aboveground tissue, while the root-associated bacterial community responded to drought.
Technical Abstract: Here we demonstrate the pseudo-protease AtFtsHi3 of Arabidopsis thaliana to be involved in drought tolerance. An AtFtsHi3 knock-down mutant (ftshi3-1(kd)) was drought-tolerant up to 20-days after the last irrigation, while wild-type wilted after 12 days. Leaves of ftshi3-1(kd) contained reduced stomata size, density and a smaller stomatic aperture. During drought stress, ftshi3-1(kd) showed lowered stomatal conductance and increased WUEi. Expression levels of ABA-responsive genes were higher in leaves of ftshi3-1(kd) than wild type; DREB1A, but not DREB2A, was significantly upregulated during drought. Even in watered conditions the mutant displayed a pale-green phenotype; further lack of FtsHi3 affected overall plant growth, photosynthetic efficiency and Darwinian fitness. A delay in seed germination of ftshi3-1(kd) was attributed to over-accumulation of ABA, ftshi3-1(kd) seedlings showed partial sensitivity to exogenous ABA. Loss of FtsHi3 also affected root length, lateral root density and the root-associated bacterial communities.