Involved in basal (BT) and acquired thermotolerance (AT), probably by preventing plasma membrane lipids peroxidation induced by severe heat-shock (HS) (PubMed:19302169, PubMed:23837879). Lipocalin that confers protection against oxidative stress caused by heat, freezing, paraquat and light (PubMed:18671872, PubMed:19302169). Confers resistance to high salt (NaCl) levels, probably by protecting chloroplasts from ion toxicity via ion homeostasis maintenance (PubMed:20959419, PubMed:24028869). Required for seed longevity by insuring polyunsaturated lipids integrity (PubMed:23837879). Translocates from cell membrane to cytoplasm upon salinity stress. A small fraction is associated with the chloroplast envelope. Expressed ubiquitously at similar levels, except in dry seeds (at protein level) (PubMed:18671872, PubMed:19302169). Present in seeds (PubMed:23837879). By drought and heat combination stress (PubMed:15047901). Accumulates upon treatment with 50 mM (beta-D -Glc)(3), a Yariv phenylglycoside that aggregates arabinogalactan-proteins (AGPs) (PubMed:15235117). The HPR motif (90-97) is required for intracellular targeting at membranes. Increased sensitivity to sudden drops in temperature and paraquat treatment. Dark-grown plants die shortly after transfer to light. These phenotypes are associated with an accumulation of hydrogen peroxide and other ROS, which causes an oxidative stress that leads to a reduction in hypocotyl growth and sensitivity to light (PubMed:18671872). Severe defects in basal (BT) and acquired thermotolerance (AT) leading to death within 7 days. Stronger sensitivity to tert-butyl hydroperoxide, a reagent that induces lipid peroxidation (PubMed:19302169). Stronger sensitivity to high salt levels (NaCl) associated with membrane injury, chlorophyll b degradation and accumulation of chloride and sodium in chloroplasts (PubMed:20959419, PubMed:24028869). When associated with disruption in CHL, highly sensitive to temperature, drought and light stresses than the single mutants, exhibiting intense lipid peroxidation. Seeds of this double mutant are very sensitive to natural and artificial aging, associated with the oxidation of polyunsaturated lipids (PubMed:23837879). Belongs to the calycin superfamily. Lipocalin family. Truncated N-terminus.