Overexpression of the rubisco activase gene improves growth and low temperature and weak light tolerance in Cucumis sativus

Abstract

Rubisco activase (RCA) is an important enzyme that can catalyze the carboxylation and oxygenation activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), which is involved in the photosynthetic carbon reduction cycle. Here, we studied the effects of changes in RCA activity on photosynthesis, growth and development, as well as the low temperature and weak light tolerance of RCA overexpressing transgenic cucumber (Cucumis sativus) plants. CsRCA overexpression increased the plant height, leaf area and dry matter, and decreased the root/top ratio in transgenic cucumber plants compared with the wild-type (WT) plants. Low temperature and low light stress led to decreases in the CsRCA expression and protein levels, the photosynthetic rate (Pn) and the stomatal conductance (Gs), but an increase in the intercellular CO (Ci) concentration in cucumber leaves. The actual photochemical efficiency and maximal photochemical efficiency of photosystem II in cucumber seedlings also declined, but the initial fluorescence increased during low temperature and weak light stress. Transgenic plants showed a lower decrease in the CsRCA expression level and actual and maximal photochemical efficiencies, as well as increases in the Ci and initial fluorescence relative to the WT plants. Low temperature and low light stress resulted in a significant increase in the malondialdehyde (MDA) content; however, this increase was reduced in transgenic plants compared with that in WT plants. Thus, the overexpression of CsRCA may promote the growth and low temperature and low light tolerance of cucumber plants in solar greenhouses.

High temperature reduces photosynthesis in maize leaves by damaging chloroplast ultrastructure and photosystem II

“…Six to ten maize plants were randomly selected and collected from different plots. Plants were killed quickly at 105°C for 30 min and then placed in an oven at 80°C for 72 hr before weighing (Bi, Liu, Jiang, & Ai, 2017).…”

Effects of endogenous ascorbic acid on resistance to high-temperature stress in excised rice leaves

“…Rubisco is an important protein in the dark reactions of photosynthesis, and its integrity and content determine the formation of photosynthetic organic compounds (Perdomo et al 2017, Bi et al 2017. Chl is important for light use in photosynthesis, and its integrity and content determine the efficiency of light reactions (Liang et al 2017).…”

Special issue in honour of Prof. Reto J. Strasser - Dorsoventral variation in photosynthesis during leaf senescence probed by chlorophyll a fluorescence induction kinetics in cucumber and maize plants

“…It has been shown that the electron transfer rate reduces during the initial phase of senescence, mainly due to a decreased content of D1 protein and cytochrome (Cyt) b6f (Holloway et al 1983, Genty et al 1989, Nath et al 2013. Leaf senescence is also accompanied by decreasing activity and content of enzymes in the Calvin cycle, with Rubisco declining most rapidly (Ishizuka et al 2004, Tholen et al 2007, Bi et al 2017, Krieger-Liszkay et al 2019.…”