Location: Soil and Water Management ResearchTitle: Overexpression of PP2A-C5 that encodes the catalytic subunit 5 of protein phosphatase 2A in Arabidopsis confers better root and shoot development under salt conditions
|Hu, Rongbin - Texas Tech University|
|Zhu, Yinfeng - Texas Tech University|
|Wei, Jia - Zhejiang Academy Of Agricultural Sciences|
|Chen, Jian - Texas Tech University|
|Huazhong, Shi - Texas Tech University|
|Guoxin, Shen - Zhejiang Academy Of Agricultural Sciences|
|Zhang, Hong - Texas Tech University|
Submitted to: Plant Cell and Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/25/2016
Publication Date: 10/28/2016
Citation: Hu, R., Zhu, Y., Wei, J., Chen, J., Huazhong, S., Guoxin, S., Zhang, H. 2016. Overexpression of PP2A-C5 that encodes the catalytic subunit 5 of protein phosphatase 2A in Arabidopsis confers better root and shoot development under salt conditions. Plant Cell and Environment. 40:150-164.
Interpretive Summary: Water availability from the Ogallala Aquifer for irrigation is decreasing on the Southern High Plains. Crops that use water more efficient are needed to sustain yields at current levels. Unfortunately there are multiple avenues to breed crops for greater water efficiency and few approaches have been attempt. Scientists have previously associated a specific plant protein with tolerance to salt. Therefore, scientists in the ARS led Ogallala Aquifer Program from Texas Tech University and Zhejiang Academy of Agricultural Sciences (China) investigated the role in root growth under salt stress. Loss of this protein through mutations decreased salt tolerance and over production improved salt tolerance. These data indicate that this specific protein affects salt tolerance and these results are of interest to plant physiologist, plant molecular biologists and plant breeders.
Technical Abstract: Protein phosphatase 2A (PP2A) is an enzyme consisting of three subunits: a scaffolding A subunit, a regulatory B subunit and a catalytic C subunit. PP2As were shown to play diverse roles in eukaryotes. In this study, the function of the Arabidopsis PP2A-C5 gene that encodes the catalytic subunit 5 of PP2A was studied using both loss-of-function and gainof- function analyses. Loss-of-function mutant pp2a-c5-1 displayed more impaired growth during root and shoot development, whereas overexpression of PP2A-C5 conferred better root and shoot growth under different salt treatments, indicating that PP2A-C5 plays an important role in plant growth under salt conditions. Double knockout mutants of pp2a-c5-1 and salt overly sensitive (sos) mutants sos1-1, sos2-2 or sos3-1 showed additive sensitivity to NaCl, indicating that PP2A-C5 functions in a pathway different from the SOS signalling pathway. Using yeast two-hybrid analysis, four vacuolar membrane chloride channel (CLC) proteins, AtCLCa, AtCLCb, AtCLCc and AtCLCg, were found to interact with PP2A-C5. Moreover, overexpression of AtCLCc leads to increased salt tolerance and Cl_ accumulation in transgenic Arabidopsis plants. These data indicate that PP2A-C5-mediated better growth under salt conditions might involve up-regulation of CLC activities on vacuolar membranes and that PP2A-C5 could be used for improving salt tolerance in crops.