Involved in chromoplast differentiation. Associated with a cellular process that triggers the differentiation of pro-plastids or other non-colored plastids into chromoplasts for carotenoid accumulation (PubMed:24267591). Is associated with carotenoid accumulation in chromoplasts (PubMed:26224804). Functions as a major regulator of the phytoene synthase PSY1 protein level and activity. Modulates carotenoid biosynthesis by means of post-transcriptional regulation of PSY1 (PubMed:25675505). Modulates carotenoid biosynthesis in part by up-regulating a series of endogenous carotenogenic genes (PubMed:25857664). Interacts with PSY1. Localizes in the nucleus in etiolated cotyledons. Its sequence is related to the DnaJ family but lacks the J domain. The CR-type-like region is similar to CR-type zinc-fingers. Belongs to the orange-like family.