Comparative transcriptomic analysis reveals key components controlling spathe color in Anthurium andraeanum (Hort.)

Anthurium andraeanum (Hort.) is an important ornamental in the tropical cut-flower industry. However, there is currently not enough information to establish a clear connection between the genetic model(s) proposed and the putative genes involved in the differentiation between colors. In this study, 18 cDNA libraries related to the spathe color and developmental stages of A. andraeanum cut-flowers were characterized by transcriptome sequencing technology. For the de novo transcriptome, a total of 114,334,082 primary sequence reads were obtained from the Illumina sequencer and were assembled into 151,652 unigenes. Approximately 58,476 transcripts were generated and used for comparative transcriptome analysis between three varieties that differ in spathe color ( Sasha (white), Honduras (red), and Rapido (purple)). A large number of differentially expressed genes (8,324) that were potentially involved in multiple biological and metabolic pathways were identified, including the flavonoid and anthocyanin biosynthetic pathways. Our results showed that chalcone synthase (CHS) and flavonoid 3-hydroxylase (F3H) were the main genes differentially expressed in the white/red/purple comparison. We also identified a differentially expressed cytochrome P450 in the late developmental stage of the purple spathe that appeared to determine the difference between the red- and purple-colored spathes. Additionally, putative MYB-domain protein candidates that could be responsible for the control of the biosynthetic pathway were identified. The results provided basic sequence information for future research on spathe color, which have important implications for breeding strategies in this ornamental. Core ideasO_LIRNA-seq was performed on three anthurium varieties. C_LIO_LIGene expression was compared for developmental stage and spathe color. C_LIO_LIDifferentially expressed unigenes were identified. C_LIO_LIPutative MYB-domain protein candidates of the anthocyanin biosynthetic pathway were identified. C_LI