Salt Stress-Induced Anthocyanin Biosynthesis Genes and MATE Transporter Involved in Anthocyanin Accumulation in Daucus carota Cell Culture.

Anthocyanins biosynthesis is a well-studied biosynthesis
pathway in Daucus carota. However, the scale-up production
at the bioreactor level and transporter involved in accumulation is
poorly understood. To increase anthocyanin content and elucidate
the molecular mechanism involved in accumulation, we examined
D. carota cell culture in flask and bioreactor for 18 days under salt
stress (20.0 mM NH4NO3/37.6 mM KNO3) at 3 day intervals.
The expression of anthocyanin biosynthesis and putative MATE
(multidrug and toxic compound extrusion) transporter expression
was analyzed by qRT-PCR. It was observed that there was a
significant enhancement of anthocyanin in the bioreactor
compared to the control culture. A correlation was observed
between the expression of MATE and the anthocyanin biosynthesis
genes (CHS, C4H, LDOX, and UFGT) on the 9th day in a bioreactor, where maximum anthocyanin accumulation and expression
was detected. We hypothesize the involvement of MATE in transporting anthocyanin to tonoplast in D. carota culture under salt
stress.