Accepted author manuscript, 3.22 MB, PDF document
Available under license: CC BY: Creative Commons Attribution 4.0 International License
Submitted manuscript
Licence: CC BY: Creative Commons Attribution 4.0 International License
Final published version
Licence: CC BY: Creative Commons Attribution 4.0 International License
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Two cowpea Rubisco activase isoforms for crop thermotolerance
AU - Gjindali, Armida
AU - Page, Rhiannon
AU - Ashton, Catherine J.
AU - Robertson, Ingrid
AU - Page, Michael
AU - Bloemers, Duncan
AU - Gould, Peter
AU - Worrall, Dawn
AU - Orr, Douglas
AU - Carmo-Silva, Elizabete
PY - 2025/6/8
Y1 - 2025/6/8
N2 - A vital crop for sub-Saharan Africa, cowpea productivity, is threatened by climate change, including increased heatwave intensity, duration and frequency. Rubisco activase (Rca) is a key molecular chaperone that maintains Rubisco activity and, due to its thermal sensitivity, is a key target for improving crop climate resilience.We identified and characterised four Rca isoforms in Vigna unguiculata cv IT97K-499-35 in vitro: Rca1β, Rca8α, Rca10α and Rca10β. Cowpea leaf and plant growth traits were also investigated during a 5-d +10°C heatwave that included assessment of Rubisco and Rca activity in leaf extracts and relative changes in the abundance of the four Rca isoforms.Cowpea Rca10α and Rca10β had higher thermal maxima, broader thermal optima and higher rates of ATP hydrolysis and Rubisco reactivation in vitro. In the absence of water deficit, the heatwave caused only mild effects, including increases in leaf temperature and expression of Rca10, small decreases in Rubisco activity and activation state and an unaltered temperature response of Rubisco activation by Rca.The superior Rca10α and Rca10β isoforms offer the prospect of enhancing the thermotolerance of cowpea and other crops in anticipation of more extreme future heatwaves.
AB - A vital crop for sub-Saharan Africa, cowpea productivity, is threatened by climate change, including increased heatwave intensity, duration and frequency. Rubisco activase (Rca) is a key molecular chaperone that maintains Rubisco activity and, due to its thermal sensitivity, is a key target for improving crop climate resilience.We identified and characterised four Rca isoforms in Vigna unguiculata cv IT97K-499-35 in vitro: Rca1β, Rca8α, Rca10α and Rca10β. Cowpea leaf and plant growth traits were also investigated during a 5-d +10°C heatwave that included assessment of Rubisco and Rca activity in leaf extracts and relative changes in the abundance of the four Rca isoforms.Cowpea Rca10α and Rca10β had higher thermal maxima, broader thermal optima and higher rates of ATP hydrolysis and Rubisco reactivation in vitro. In the absence of water deficit, the heatwave caused only mild effects, including increases in leaf temperature and expression of Rca10, small decreases in Rubisco activity and activation state and an unaltered temperature response of Rubisco activation by Rca.The superior Rca10α and Rca10β isoforms offer the prospect of enhancing the thermotolerance of cowpea and other crops in anticipation of more extreme future heatwaves.
U2 - 10.1111/nph.70271
DO - 10.1111/nph.70271
M3 - Journal article
JO - New Phytologist
JF - New Phytologist
SN - 0028-646X
ER -