carotenoid-metabolism
Carotenoid metabolism encompasses the biosynthetic and degradative pathways that produce and modify carotenoids — the yellow, orange, and red pigments found in plant tissues. These compounds play essential roles in photosynthesis, photoprotection, and the production of abscisic acid, a key hormone regulating stress responses and development. Understanding carotenoid metabolism enables researchers to improve crop nutritional quality, stress tolerance, and floral or fruit coloration through targeted breeding and genetic engineering.
PubMed · 2026-04-09
Researchers discovered that a single enzyme called LOX2 in tobacco plants acts as a master controller, simultaneously breaking down color pigments (carotenoids) and ramping up the plant's stress-alarm chemical (methyl jasmonate). Manipulating this one gene could improve both how resilient plants are to stress and how flavorful crops taste.
Silencing LOX2 increased levels of four key carotenoids (β-carotene, lutein, violaxanthin, neoxanthin) plus both forms of chlorophyll, making plants greener and more pigment-rich.
Overexpressing LOX2 elevated methyl jasmonate and 2-Hexenal (a green, grassy volatile) levels compared to wild-type plants, while also upregulating the genes responsible for making these compounds.
LOX2 was identified as the dominant isoform in the 13-LOX subfamily in tobacco and is strongly induced by methyl jasmonate treatment, revealing a self-amplifying feedback loop.
