Proline accumulation in wheat seedlings exposed to zinc and copper

Zinc stress induces physiological, ultra-structural and biochemical changes in mandarin orange (Citrus reticulata Blanco) seedlings

“…Accumulation of proline is an indication of protection for plants under environmental stresses (Chen et al 2003). Increases in proline as a function of metal accumulation had been observed in response to heavy metals, including Zn (Bassi and Sharma 1993). Zn deficiency and excess stimulated accumulation of proline, which apart from acting as a metal chelator and osmolyte, scavenges hydroxyl radical (OH • ) and 1 O 2 and thus provides protection against ROS induced cell damage (Radić et al 2009) to some extent.…”

Inoculation with mycorrhizal fungi modifies proline metabolism and increases chromium tolerance in pepper plants (Capsicum annuum L.)

“…Moreover, it was observed that many plants accumulate proline when were treated with toxic concentrations of heavy metals (Bassi and Sharma, 1993;Costa and Morel, 1994;Schat and Vooijs, 1997). The effect of HM on proline synthesis is contradictory.…”

Role of proline under changing environments

“…[3][4][5] These include proline, sucrose, polyols, trehalose and quaternary ammonium compounds (QACs) such as glycine betaine, alinine betaine, proline betaine and pipecolate betaine. 6,7 The phenomenon of proline accumulation is known to occur under water deficit, 8 salinity, 9,10 low temperature, 11 heavy metal exposure [12][13][14][15] UV radiations, etc. Apart from acting as an osmolyte for osmotic adjustment, proline contributes to stabilizing sub-cellular structures (e.g., membranes and proteins), scavenging free radicals and buffering cellular redox potential under stress conditions.…”

“…Many plants have been shown to accumulate proline when exposed to heavy metal stress. 12,13,63,119,120 Besides acting as an osmoprotectant and ROS quencher, proline also acts as a heavy metal chelator, thereby alleviating heavy metal stress. 121 Proline induces the formation of phytochelatins which chelate with heavy metals like Cd thereby decreasing their toxicity.…”

“…Enhanced proline accumulation was noted in response to heavy metals like Cd, Co, Zn and Pb in Cajanus cajan and Vigna mungo; 119 Pb, Cd, Cu and Zn in Helianthus annuus; 127 and Zn and Cu in Triticum aestivum. 13 Proline accumulation in response to heavy metal exposure has been observed in lower plants, e.g., algae. Proline accumulated when different algae were exposed to metals such as Cu in Anacystis nidulans, 128 Chlorella sp.…”