Genome-wide transcription factors identification and transcriptome analysis of root development in Taraxacum...

As a promising alternative source of natural rubber production, Taraxacum kok-saghyz Rodin (TKS) demonstrates significant rubber biosynthesis capacity in its root system. To elucidate the transcriptional regulation of rubber biosynthesis, we conducted a comprehensive genome-wide identification of transcription factors (TFs) and their temporal expression patterns during root development. Through genome-wide analysis, we identified 2095 transcription factors (TFs) distributed among 68 families in TKS; with the AP2/ERF-ERF family being the largest, comprising 169 members. RNA-seq profiling across developmental stages (10-80 DAP) revealed distinct spatiotemporal expression patterns. TF expression was initially elevated in young stems, while root-specific TFs, particularly from the WRKY family, peaked at 72 DAP. Sixteen root-enriched TF candidates were functionally validated for tissue specificity, with TkA01G586780 emerging as a key regulator showing elevated expression in mature taproots, transcriptional autoactivation capability in yeast, and activates promoter regions of three mevalonate pathway genes (ACAT3, HMGR6, MVK3) essential for rubber biosynthesis. This study provides the first systematic characterization of TKS transcription factors, revealing critical regulatory networks governing root development and rubber biosynthesis. Our findings establish valuable genomic resources for molecular breeding strategies to enhance rubber yield in this industrially significant alternative crop.