Identification and Expression Analysis of <i>AP2/ERF</i> Gene Family Members in Different Growth Periods of <i>Magnolia officinalis</i>

Magnolia officinalis is a perennial deciduous tree that has medicinal properties. The AP2/ERF gene family has a number of roles in long-term growth and metabolism. The expression of this function varies with the growth period. In this work, based on the transcriptome data of Magnolia officinalis, the complete coding gene of Magnolia officinalis was obtained, and the corresponding protein sequence was retrieved from NCBI and compared with the model plant Arabidopsis thaliana. After screening, 75 protein sequences from the AP2/ERF gene family were identified and called MoAP2/ERF1–MoAP2/ERF75, followed by bioinformatics analysis. 75 AP2/ERF gene families were found and classified into four subfamilies. Their protein architectures had one or more conserved AP2 domains, which were typically unstable and hydrophilic. Subcellular research revealed that it was primarily located in the nucleus. Among them, the DREB subfamily showed stronger activity in the early growth period of Magnolia officinalis, suggesting that Magnolia officinalis had stronger resistance to adversity during this period. The 15 members of the MoAP2/ERF gene family showed significant differences during different growth periods, and they regulated the gene expression of Magnolia officinalis by binding to DNA. The 15 MoAP2/ERF gene families have a wide range of physiological activities in biological processes, cellular components, and molecular functions. Including MoAP2/ERF55 can catalyze imidazole glycerol phosphate synthase activity; MoAP2/ERF39 acts as a transcriptional activator of Pti6.