Induction of carotenogenesis in cultured cells of Lycopersicon esculentum

Abstract

The bioregulator 2-(4-chlorophenyl-thio) triethylamine (CPTA) which is known to induce lycopene formation and chromoplast differentiation in immature tomato fruits, was tested for its ability to bring about carotenogenesis in suspension cultures of tomato cells ( Lycopersicon esculentum cv. EP-7). Untreated dark-grown cultured tomato cells contain low levels of carotenoids, of which lycopene and β-carotene are the most abundant. The addition of CPTA to the culture medium brought about over a 60-fold increase in their total carotenoids during a 14-day culture period. The carotenoid content of the cells increased at a constant rate throughout the log phase of growth and this increase was brought about primarily by the accumulation of lycopene. When CPTA was given to logarithmically growing cells, carotenoid accumulation began after a 3-h lag period. This CPTA-heximide increase in carotenoids could be blocked by simultaneous cycloheximide (CH) treatment at concentrations of this drug which were shown to block [ 3H] leucine incorporation into protein.