Engineering Rubisco activase from thermophilic cyanobacteria into high-temperature sensitive plants

Abstract

In the past decade, various strategies to improve photosynthesis and crop yield, such as leaf morphology, light interception and use efficiency, biochemistry of light reactions, stomatal conductance, carboxylation efficiency, and source to sink regulation, have been discussed at length. Leaf morphology and physiology are tightly coupled to light capturing efficiency, gas exchange capacity, and temperature regulation. However, apart from the photoprotective mechanism of photosystem-II (PSII), i.e. non-photochemical quenching, very low genetic variation in the components of light reactions has been observed in plants. In the last decade, biochemistry-based enhancement of carboxylation efficiency that improves photosynthesis in plants was one of the potential strategies for improving plant biomass production. Enhancement of activation of the ubiquitous enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco; EC 4.1.1.39) by Rubisco activase may be another potential strategy for improving a photosynthesis-driven increase in crop yield. Rubisco activase modifies the conformation of the active center in Rubisco by removing tightly bound inhibitors, thereby contributing to enzyme activation and rapid carboxylation. Thermophilic cyanobacteria are oxygenic photosynthetic bacteria that thrive in high-temperature environments. This critical review discusses the prospects for and the potential of engineering Rubisco activase from thermophilic cyanobacteria into temperature-sensitive plants, to increase the threshold temperature and survival of these plants in arid regions.

Wheat (Triticum Aestivum L.) Production Under Drought and Heat Stress – Adverse Effects, Mechanisms and Mitigation: A Review

“…However, yield stability is better to stress tolerance indicator under heat stress or water stress conditions (Fleury et al, 2010). In addition, a little progress has been made in identifying key mechanisms associated with high yield and stress tolerance against high temperature and drought stress (Ogbaga et al, 2018).…”

“…Xia (2012) reported that heat, as well as drought stress tolerance, was positively associated with photosynthetic capacity. Recently, Ogbaga et al (2018) suggested that developing thermos-tolerance in photosynthetic machineries such as in rubisco or rubisco activase will result in enhanced crop productivity. Stay-green plants have been used to select for yield stability and a selection criterion for heat stress tolerance in wheat (Joshi et al, 2007;Christopher et al, 2008).…”

Linking changes in chlorophyll a fluorescence with drought stress susceptibility in mung bean [Vigna radiata (L.) Wilczek]

“…Drought stress reduces plant growth by impairing numerous physiological processes. Photosynthesis is the main physiological process affected by drought and is a hot topic under discussion over the past two decades (Athar & Ashraf, 2005; Lawlor & Tezara, 2009; Lawlor & Uprety, 1993; Ogbaga et al, 2018; Tezara et al, 1999). Drought stress reduced the photosynthetic activity by closing the stomata, thereby decreasing CO 2 influx and fixation in the Calvin cycle.…”

Is Photoprotection of PSII One of the Key Mechanisms for Drought Tolerance in Maize?

“…Drought-tolerant plants or drought-tolerant cultivars of same species had a better ability to maintain physiological activities such as CO 2 assimilation rate, nutrient uptake, etc., at low-water status [4]. Since plant growth and yield mainly depend on plant photosynthetic activity, several researchers are of the view that selection of cultivars/varieties based on photosynthetic traits may help in developing high-yielding and stress-tolerant crop cultivars [5][6][7][8][9][10]. Most of the studies have focused on improving the activity of rubisco with enhanced CO 2 fixation, or lowering carbon loss through photorespiration [7][8][9][10].…”