@Article{phyton.2026.083737,
AUTHOR = {Renjie Li, Ruiya Li, Yuying Li, Lili Guo, Qi Guo, Xiangnan He, Yunxin Zhou, Xiaogai Hou},
TITLE = {<i>PsSEP3L1</i> Positively Regulates Petal Number in Tree Peony (<i>Paeonia suffruticosa</i>) by Interacting with MADS-Box Family Proteins},
JOURNAL = {Phyton-International Journal of Experimental Botany},
VOLUME = {},
YEAR = {},
NUMBER = {},
PAGES = {{pages}},
URL = {http://www.techscience.com/phyton/online/detail/27109},
ISSN = {1851-5657},
ABSTRACT = {<i>SEP3</i>, one of the SEPALLATA (SEP) genes, plays a crucial role in the regulation of floral organ morphogenesis in plants. However, its specific function and molecular regulatory mechanisms remain largely unclear in tree peony (<i>Paeonia suffruticosa</i> Andr.). In this study, the <i>PsSEP3L1</i> sequence of the tree peony cultivar ‘Luoyang Hong’ was obtained by homologous cloning. The open reading frame of <i>PsSEP3L1</i> is 738 bp and encodes 245 amino acids. Phylogenetic analysis indicated that PsSEP3L1 was most closely related to the SEP3 homolog from <i>cassava</i>. The expression level of <i>PsSEP3L1</i> in petals, petaloid petals, and stamens was significantly higher than that in sepals. Specifically, in the petaloid petals of the tree peony cultivar ‘Luoyang Hong’, the expression level was 23.73-fold higher than that in sepals. Functional assays demonstrated that overexpression of <i>PsSEP3L1</i> significantly increased petal number in tree peony, whereas silencing of this gene resulted in a significant reduction in petal number, confirming its positive regulatory role in petal number determination. The Yeast two-hybrid and Bimolecular fluorescence complementation assays revealed that PsSEP3L1 protein interacts with MADS-box family proteins, including PsSEP1L, PsAP3, and PsAG. Collectively, <i>PsSEP3L1</i> may participate in regulating petal number in tree peony by forming protein complexes with other MADS-box proteins, thereby contributing to floral organ morphogenesis. This study provides a basis for further mechanistic studies on floral organ morphogenesis in tree peony.},
DOI = {10.32604/phyton.2026.083737}
}