Gibberellins (GAs), enzymes that play a significant role in plant growth and development, and their levels in plants could be regulated by gibberellin-oxidases (GAoxs). As important fruit trees and ornamental plants, the study of the mechanism of plant architecture formation of the Prunus genus is crucial. Here, 85 GAox genes were identified from P. mume, P. armeniaca, P. salicina, and P. persica, and they were classified into six subgroups. Conserved motif and gene structure analysis showed that GAoxs were conserved in the four Prunus species. Collinearity analysis revealed two fragment replication events of PmGAoxs in the P. mume genome. Promoter cis-elements analysis revealed 24 PmGAoxs contained hormone-responsive elements and development regulatory elements. The expression profile indicated that PmGAoxs have tissue expression specificity, and GA levels during the dormancy stage of flower buds were controlled by certain PmGAoxs. After being treated with IAA or GA₃, the transcription level of PmGA2ox8 in stems was significantly increased and showed a differential expression level between upright and weeping stems. GUS activity driven by PmGA2ox8 promoter was detected in roots, stems, leaves, and flower organs of Arabidopsis. PmGA2ox8 overexpression in Arabidopsis leads to dwarfing phenotype, increased number of rosette leaves but decreased leaf area, and delayed flowering. Our results showed that GAoxs were conserved in Prunus species, and PmGA2ox8 played an essential role in regulating plant height.

Prunus mume, a traditional ornamental species native to China, is highly valued for both its captivating weeping variety and economic value. The glycosylation of metabolites, which is mediated by UDP-glycosyltransferases (UGTs), is essential for the regulation of secondary metabolic pathways in plants. Here, we systematically identified and analyzed the UGTs in P. mume. A total of 182 PmUGTs were identified using genomic data and categorized into 16 distinct subfamilies (A–P). All PmUGTs were distributed unevenly across the eight chromosomes, with clear evidence of tandem duplication. Additionally, synteny analysis revealed a close evolutionary relationship between P. mume and Prunus persica. A promoter cis-acting element analysis indicated that PmUGTs may respond to light, hormones, and external stresses. A heatmap analysis revealed that PmUGTs had specific expression patterns across different tissues, under various hormone treatments, and in different developmental stages of stem lignification. Notably, qRT-PCR verification showed significant differences in PmUGT163 expression between straight and weeping stems, underscoring its role in regulating plant architecture formation. Taken together, our study elucidates the evolutionary trajectory of PmUGTs and lays the groundwork for the further validation of the candidate genes involved in plant architectural formation.