Phylogenetic and Expression Analysis of SBP-Box Gene Family to Enhance Environmental Resilience and Productivity in Camellia sinensis cv. Tie-guanyin

Tieguanyin tea, a renowned oolong tea, is one of the ten most famous teas in China. The Squamosa Promoter Binding Protein (SBP)-box transcription factor family, widely present in plants, plays a crucial role in plant development, growth, and stress responses. In this study, we identify and analyze 22 <i>CsSBP</i> genes at the genome-wide level. These genes were distributed unevenly across 11 chromosomes. Using <i>Arabidopsis thaliana</i> and <i>Solanum lycopersicum</i> L. as model organisms, we constructed a phylogenetic tree to classify these genes into six distinct subfamilies. Collinearity analysis revealed 20 homologous gene pairs between <i>AtSBP</i> and <i>CsSBP</i>, 21 pairs between <i>SiSBP</i> and <i>CsSBP</i>, and 14 pairs between <i>OsSBP</i> and <i>CsSBP.</i> Cis-acting element analysis indicated that light-responsive elements were the most abundant among the <i>CsSBP</i> genes. Protein motif, domain, and gene architecture analyses demonstrated that members of the same subgroup shared similar exon-intron structures and motif arrangements. Furthermore, we evaluated the expression profiles of nine <i>CsSBP</i> genes under light, shade, and cold stress using qRT-PCR analysis. Notably, <i>CsSBP1, CsSBP17</i>, and <i>CsSBP19</i> were significantly upregulated under all three stresses. This study provides fundamental insights into the <i>CsSBP</i> gene family and offers a novel perspective on the mechanisms of SBP transcription factor-mediated stress responses, as well as Tieguanyin tea's adaptation to environmental variations.