SRA

Abstract: Chimonanthus praecox is an important ornamental plant, and its petal color is an important ornamental trait and a crucial basis for variety classification. The different colors of wax plum petals are caused by the accumulation of specific flavonoid metabolites, but the molecular mechanism of their specific accumulation in different petal cells is still unclear. Here, we are conducting single-nucleus RNA-sequencing (snRNA-seq) research on the understanding of the molecular mechanisms underlying flower color formation in C. praecox petals. We isolated 13073 and 12625 single-cell nuclei from the inner and outer petals, divided them into 14 cell clusters and 5 cell types, and constructed a single-cell transcriptome map of the petals. Differential expression gene analysis reveals that gene expression levels have cell specificity. Interestingly, the pseudo-time analysis of epidermal cells revealed that genes such as the anthocyanin synthesis pathway genes ANS and UGT were almost not expressed in the early and late stages of petal cell development, while the expression levels of the flavonol metabolism pathway genes PAL, 4CL, and FLS significantly increased during development, indicating that the regulation of cell development may be the key to determining the color fate of inner and outer petals. Overall, we have established a single-cell transcriptional landscape map of C. praecox petals, laying the foundation for understanding plant flower organ development and pigment cell specific accumulation.