Anotación genómica de genes expresados en la biosíntesis de compuestos fenólicos en pitahaya (Hylocereus spp.) expuesta a condiciones de estrés

Abstract

The lack of complete genetic information on the pitaya (Hylocereus spp.) genome and the absence of annotations in biological databases hinder the precise identification of genes expressed under stress conditions. To address this challenge, this study focused on annotating genes involved in the biosynthesis of phenolic compounds in pitaya under biotic (pathogen infection) and abiotic (flowering induction with supplementary light) stress conditions. Using various bioinformatic techniques, transcriptomic data were analyzed to assemble de novo sequences from raw reads for each stress condition. The quality of these assemblies was rigorously evaluated, and a consensus sequence was generated to analyze its homology with related species. Structural and functional annotation of the assemblies was conducted using ab initio and de novo prediction tools, resulting in annotations in GFF3 format that detail both the structure and biological functions of the predicted genes. Subsequently, a differential expression analysis (DEG) was performed to identify genes expressed in the biosynthesis of phenolic compounds under different stress conditions. The results revealed nine key enzymes involved in the metabolic pathways of phenylpropanoids, flavonoids, and anthocyanins. Additionally, a MYB transcription factor that regulates gene expression in these pathways was identified. This research underscores the complexity of pitaya's adaptive mechanisms in response to stress, highlighting its activation of specific biosynthetic processes that enhance antioxidant capacity and adaptive ability under adverse conditions.