Identification and Expression Analysis of the Magnolia officinalis AP2/ERF Gene Family Based on Different Age Groups

Objective The purpose of this study was to identify the AP2/ERF gene family in Magnolia officinalis (M. officinalis) and to examine changes in AP2/ERF gene expression and functional annotation as M. officinalis grows. Methods The transcriptome data of M. officinalis were evaluated and compared to those of the model plant Arabidopsis thaliana . After screening, 75 distinct AP2/ERF gene family sequences (Ho AP2/ERF 1 ~ Ho AP2/ERF 75) were identified and analyzed via bioinformatics methods. The expression levels of XR and DR in the two groups were determined using Heatmap Tree, and genes with substantial expression were examined and functionally annotated. Results The 75 Ho AP2/ERF proteins all had one or more conserved AP2 domains. Its protein stability is usually indicative of an unstable protein. Ho AP2/ERF family proteins are hydrophilic. Subcellular research revealed that it was primarily located in the nucleus. The expression levels of certain AP2/ERF genes differed considerably across the XR and DR groups, with XR being overexpressed compared to those in the DR group. Conclusion M. officinalis' AP2/ERF gene family is divided into four subfamilies. Its role not only is related to M. officinalis growth and development, as well as secondary metabolism but also affects its stress tolerance. Furthermore, the low-aged group of M. officinalis XR exhibited greater stress tolerance than did the high-aged group of M. officinalis DR. Among the significantly expressed genes, Ho AP2/ERF 55 controls the activity of imidazole glycerol phosphate synthase, while Ho AP2/ERF 39 plays a role in plant–pathogen interactions by regulating the expression of PR genes.