Enhancement of tolerance of abiotic stress by metabolic engineering of betaines and other compatible solutes

Ecophysiological leaf traits of native and exotic palm tree species under semi-arid conditions

“…Thus, the balance between the carbon gain through photosynthesis and the use of assimilates was affected during dry period conditions, leading to changes in sugar content (Pinheiro and Chaves 2011). The content of other compatible solutes, such as FAA, also increased as a consequence of drought only in A. aculeata (Chen and Murata 2002). The maintenance of photosynthetic activity even during periods of low rainfall is an advantage for evergreen species compared with deciduous species.…”

Up-regulation of antioxidant and glyoxalase systems by exogenous glycinebetaine and proline in mung bean confer tolerance to cadmium stress

“…Although the mechanism by which metals cause plant injury is not clearly understood, there is increasing evidence that, at least in part, metal toxicity is due to oxidative damage (Chao and Seo 2005;Hsu and Kao 2007a;Hu et al 2009). One strategy for improving tolerance to Cd is altered cellular metabolism leading to accumulation of particular solutes that include nitrogen-containing compounds, such as proline and other amino acids, polyamines and quaternary ammonium compounds like betaine that stabilize proteins or stress proteins that protect plants to reduce the content of undesired heavy metals (Chen and Murata 2002). Proline and betaine accumulation in plants under metal stress has been widely reported (Sun et al 2007;Costa and Morel 1994;Tamas et al 2008).…”

Regulation of phosphatidylcholine biosynthesis under salt stress involves choline kinases in Arabidopsis thaliana

“…Whole rosettes (0.5 g fresh weight) from control and from 24-or 48-h treated plants were cut in fragments using a razor blade and placed in small vials containing 0.5Â MS, supplemented with either 0.5 lCi/ml [methyl- 14 ), whereas the aqueous metabolites in the Cho labeling experiment were separated by TLC with the solvent mixture containing methanol, 0.5% NaCl, ammonium hydroxide (50:50:1, v/v). Radiolabeled metabolites were visualized using a PhosphorImager scanner (Molecular Dynamics), identified relatively to the migration of commercial standards spotted on the same plates and the label incorporation associated with each compound was determined by scraping appropriate areas prior to scintillation counting.…”

“…Although related to Cho metabolism, the adaptive accumulation of GB is not accompanied by a change in the net PC biosynthesis rate [13]. Much effort has been undertaken to improve stress resistance in model species, such as tobacco and Arabidopsis, that do not possess the Cho monooxygenase nor the betaine aldehyde dehydrogenase enzymes necessary for GB biosynthesis (see [14] for a review). In Cho monooxygenase transgenic tobacco, significant accumulation of GB occurs only after exogenous Cho supply or by engineering plants to overproduce Cho, and it appears that Cho biosynthesis is a major limiting factor in GB synthesis [13,[15][16][17].…”