Genome-Wide Identification and Expression Profiling of Phosphatidylethanolamine-Binding Protein (PEBP) Genes in Helianthus annuus L.

The phosphatidylethanolamine-binding protein (PEBP) gene family is critical for regulating plant growth, development, and flowering. Sunflower (Helianthus annuus L.) is the fourth most important oilseed crop globally. However, the genomic structure and functional diversity of PEBP genes in sunflower remain unexplored. Leveraging the recently assembled telomere-to-telomere (T2T) sunflower genome, a genome-wide analysis of the HaPEBP family was carried out. A total of 12 PEBP genes were identified in sunflower and categorized into three subfamilies: TFL1-like, FT-like, and MFT-like. Phylogenetic and synteny analyses revealed that tandem duplication events have substantially contributed to the evolution and expansion of the HaPEBP gene family. Furthermore, the analysis of the promoter regions revealed 77 distinct cis-acting elements, including 35 related to light signaling and growth regulation, highlighting their potential involvement in the regulation of flowering and development in sunflower. Expression profile analysis using RNA-seq data across various tissues indicated that FT-like and TFL1-like HaPEBP genes may be the key regulators of flowering time and plant architecture in sunflower varieties. This study offers valuable insights into the structural, evolutional, and functional dynamics of the HaPEBP gene family and holds significant implications for sunflower breeding strategies aimed at optimizing flowering time and plant architecture traits.