Cloning of PoAIL6 Gene Related to Somatic Embryogenesis in Paeonia ostii ‘Fengdan’

<i>AINTEGUMENTA-LIKE6</i> (<i>AIL6</i>) is a transcription factor specifically expressed in embryos. It is a key to improving peony regeneration through tissue culture. Based on transcriptomic data from our previous research and the published genome data of <i>Paeonia ostii,</i> we identified the <i>PoAIL6</i> gene associated with somatic embryogenesis (SE) in <i>Paeonia ostii</i> 'Fengdan'. Structural and phylogenetic analyses were conducted on the <i>PoAIL6</i>-encoded protein, and its expression pattern across tissues and embryo developmental stages were explored using real-time quantitative PCR. Our results revealed that <i>PoAIL6</i> contained two AP2 conserved domains and the characteristic motif of <i>AIL6</i> genes. Phylogenetic analysis revealed that the <i>PoAIL6</i> gene has similarity to grape (<i>Vitis vinifera</i>) and cocoa (<i>Theobroma cacao</i>). <i>PoAIL6</i> exhibited the highest expression during early embryonic development, with expression levels gradually decreasing throughout SE progression. It was most highly expressed in peony seeds and showed relatively high expression in callus tissue. This study underscores the pivotal role of <i>PoAIL6</i> in the early SE and lays a playground for elucidating its molecular mechanisms, supporting the development of efficient and stable regeneration and transformation systems in peony.