biostudies-literatureUnknown15Sun YPIN-FORMED (PIN) proteins, which function as efflux transporters, play many crucial roles in the polar transportation of auxin within plants. In this study, the exogenous applications of auxin IAA and TIBA were found to significantly prolong and shorten the florescence of tree peony (<i>Paeonia suffruticosa</i> Andr.) flowers. This finding suggests that auxin has some regulatory influence in petal senescence and abscission. Further analysis revealed a total of 8 <i>PsPINs</i> distributed across three chromosomes, which could be categorized into two classes based on phylogenetic and structural analysis. PsPIN1, PsPIN2a-b, and PsPIN4 were separated into the "long" PIN category, while PsPIN5, PsPIN6a-b, and PsPIN8 belonged to the "short" one. Additionally, the cis-regulatory elements of <i>PsFrontiers in plant science1380417https://www.ebi.ac.uk/biostudies/studies/S-EPMC11116700biostudies-literatureAuxin efflux carrier PsPIN4 identified through genome-wide analysis as vital factor of petal abscission.PMC11116700Fang YGai SChen JZhang YMao XLiu CSun YJiang NZhang QSun ZYuan YfalseAuxin efflux carrier PsPIN4 identified through genome-wide analysis as vital factor of petal abscission.PIN-FORMED (PIN) proteins, which function as efflux transporters, play many crucial roles in the polar transportation of auxin within plants. In this study, the exogenous applications of auxin IAA and TIBA were found to significantly prolong and shorten the florescence of tree peony (<i>Paeonia suffruticosa</i> Andr.) flowers. This finding suggests that auxin has some regulatory influence in petal senescence and abscission. Further analysis revealed a total of 8 <i>PsPINs</i> distributed across three chromosomes, which could be categorized into two classes based on phylogenetic and structural analysis. PsPIN1, PsPIN2a-b, and PsPIN4 were separated into the "long" PIN category, while PsPIN5, PsPIN6a-b, and PsPIN8 belonged to the "short" one. Additionally, the cis-regulatory elements of <i>Ps2024-01-01T00:00:00Z20242026-04-25T03:26:41.384Z2026-04-25T03:22:07.653ZS-EPMC111167003879909410.3389/fpls.2024.1380417