Methyl jasmonate- or gibberellins A 3-induced astaxanthin accumulation is associated with up-regulation of transcription of β-carotene ketolase genes ( bkts) in microalga Haematococcus pluvialis

Abstract

The microalga Haematococcus pluvialis accumulates astaxanthin in response to abiotic stresses . Since methyl jasmonate (MJ) and gibberellins A 3 (GA 3) are involved in the stress responses of plants, the impact of these compounds on astaxanthin metabolism was studied. Alga cells treated separately with MJ and GA 3 accumulated more astaxanthin than the controls. MJ and GA 3 treatment increased the transcription of three β-carotene ketolase genes ( bkts). MJ- and GA 3-responsive cis-acting elements were identified in the 5′-flanking regions of bkt genes. These results suggest that MJ and GA 3 constitute molecular signals in the network of astaxanthin accumulation. Induction of astaxanthin accumulation by MJ or GA 3 without any other stimuli presents an attractive application potential.