Genome-Wide Analysis of Transcription Factor Gene Family and Gene Expression Profiles during Anthocyanin Synthesis in Common Walnut ( L.).

The gene family, encoding plant transcriptional regulators, participates in many metabolic pathways of plant physiology and development, including flavonoid metabolism and anthocyanin synthesis. This study proceeded as follows: the gene family was analyzed genome-wide, and the family members were identified and characterized using the high-quality walnut reference genome "Chandler 2.0". All 204 were established and categorized into 30 subgroups via phylogenetic analysis. were unevenly distributed over 16 chromosomes. Most had similar structures and conservative motifs. The -acting elements exhibit multiple functions of such as light response, metabolite response, and stress response. We found that the expansion of was mainly caused by WGD or segmental duplication events. Ka/Ks analysis indicated that these genes were in a state of negative purifying selection. Transcriptome results suggested that were widely entangled in the process of walnut organ development and differentially expressed in different colored varieties of walnuts. Subsequently, we identified 17 differentially expressed , 9 of which may regulate anthocyanin biosynthesis based on the results of a phylogenetic analysis. These genes were present in greater expression levels in 'Zijing' leaves than in 'Lvling' leaves, as revealed by the results of qRT-PCR experiments. These results contributed to the elucidation of the functions of in walnut coloration. Collectively, this work provides a foundation for exploring the functional characteristics of the in walnuts and improving the nutritional value and appearance quality of walnuts.