Fig. 9
From: Improving the anthocyanin accumulation of hypocotyls in radish sprouts by hemin-induced NO
A model of how hemin induce anthocyanin accumulation in the hypocotyls of radish sprouts. Hemin probably act as a HO-1 inducer to increase NIA and NOA1 gene expression and enhance NR and NOS activities, and thereby promotes NO production. NO may induce HO-1 heme oxygenase-1 gene expression (as revealed in human muscle cell line and murine macrophage-like cell line) to form a positive feedback loop with HO-1. NO signalling probably up regulates the expression of transcription factors (PAP1 and PAP2), which could activate the transcriptions of anthocyanin biosynthesis related structural genes, and lead to anthocyanin accumulation. The measurement resolution of the image was 1388*1044. Bar = 50 μm