Genome-wide identification of Alfin Like (AL) transcription factors and their regulatory role in abiotic stress responses in Poplar (Populus trichocarpa)

Poplar is a valuable natural resource that is extensively utilized to manufacture many types of paper and wood products. It has considerable economic and ecological importance. However, forest dieback caused by environmental stressors has been increasing in recent years. Abiotic stress is managed by the Alfin-like (AL) gene in plants. The highly conserved DUF3594 domain and PHD-finger motif, which belong to the family Alfin-like transcription factors (AL-TFs), are essential for the metabolic and physiological reactions of plants to abiotic stress. Although the environmental stress sensitivity of AL-TFs has not yet been elucidated, these TFs play a vital role in regulating plant growth. We performed a database search and discovered 9 AL TFs. Using the AL-protein sequences from a variety of plant species, gene structures as well as conserved amino acid sequences, cis-elements of promoter regions, and events in the evolution of genes were examined. A phylogenetic tree was constructed and divided into six distinct groups. The expression of PtAL genes was specific to certain organs, and their gene mapping reveled that these genes are situated on seven out of the nineteen chromosomes present in Populus trichocarpa. Moreover, the majority of PtAL genes were strongly expressed in response to abiotic conditions such as low temperature (4 °C), high temperature (39 °C), salt (100 mM NaCl solution), and drought (Water holding). Two PtAL genes (PtAL4 and PtAL6) were sensitive to all abiotic stressors evaluated. The highly expressed PtAL genes (PtAL5 and PtAL7) discovered in this study could be employed in the Populus breeding program to generate stress-resistant cultivars. Our research shows that PtAL genes are very important for plant growth and development and for their ability to cope with environmental stress. This discovery offers valuable insights for improving plant stress tolerance.