Development and carotenoid synthesis in dark-grown carrot taproots require PHYTOCHROME RAPIDLY REGULATED1

• DOI: 10.1093/plphys/kiac097
• Publication Date: 2022-03-09T20:11:05Z
• Authors: Daniela Arias; Angélica Ortega; Christian Gonzále...; Luis Felipe Quiroz; Jordi Moreno-Romero; Jaime F Martínez-...; Claudia Stange
• Keywords: Taproot; Photomorphogenesis; Daucus carota; Phytochrome; Terminator (solar); Phytochrome A

Light stimulates carotenoid synthesis in plants during photomorphogenesis through the expression of PHYTOENE SYNTHASE (PSY), a key gene biosynthesis. The orange carrot (Daucus carota) synthesizes and accumulates high amounts carotenoids taproot that grows underground. Contrary to other organs, light impairs development represses carotenogenic genes, such as DcPSY1 DcPSY2, reducing accumulation. By means RNA sequencing, previous analysis, we observed PHYTOCHROME RAPIDLY REGULATED1 (DcPAR1) is more highly expressed underground grown compared with those light. PAR1 transcriptional cofactor negative role shade avoidance syndrome regulation Arabidopsis (Arabidopsis thaliana) dimerization PHYTOCHROME-INTERACTING FACTORs (PIFs), allowing moderate carotenoids. Here, show overexpressing AtPAR1 increases production taproots well expression. DcPAR1 led us hypothesize functional was verified vivo binding AtPIF7 overexpression Arabidopsis, where AtPSY accumulation increased together photomorphogenic phenotype. Finally, antisense lines presented dramatic decrease levels relative genes impaired development. These results suggest factor for secondary root