Comprehensive characterization of potato TBL genes reveals candidates for salt and drought stress tolerance

The <i>Trichome Birefringence-Like</i> (<i>TBL</i>) gene family encodes polysaccharide acetyltransferases that modify polysaccharide properties, playing key roles in trichome development, cell wall acetylation, and responses to biotic and abiotic stresses. Potato, a globally important crop, frequently faces salinity and drought stress. However, the role of the potato <i>TBL</i> gene family in stress resistance remains unexplored. Using bioinformatics, we identified 72 St<i>TBL</i> genes in the potato DM1-3-516 R44 genome, unevenly distributed across 12 chromosomes. Phylogenetic analysis grouped them into three subfamilies with conserved domains including PC-Esterase, PMR5N, and DUF4283. We further examined gene structure, promoter cis-elements, predicted miRNA targets, GO annotations, and tissue-specific expression. Under both salt and drought stress, we identified several responsive candidate genes from the 72 <i>StTBLs</i>: 10 potential salt-responsive candidates (<i>StTBL 1</i>, <i>StTBL 3</i>, <i>StTBL 16</i>, <i>StTBL 20</i>, <i>StTBL 22</i>, <i>StTBL28</i>, <i>StTBL 58</i>, StTBL 59, <i>StTBL 60</i> and <i>StTBL 68</i>) and 11 potential drought-responsive candidates (<i>StTBL 1</i>, <i>StTBL 2</i>, <i>StTBL 3</i>, <i>StTBL 12</i>, <i>StTBL 19</i>, <i>StTBL 21</i>, <i>StTBL 22</i>, <i>StTBL 28</i>, <i>StTBL31</i>, <i>StTBL 33</i> and <i>StTBL 69</i>). This study presents the first genome-wide characterization of the <i>TBL</i> gene family in potato. The findings highlight candidate genes for improving salt and drought tolerance, offering insights for developing stress-resilient potato.