Evolutionary and Integrative Analysis of Gibberellin-Dioxygenase Gene Family and Their Expression Profile in Three Rosaceae Genomes (, , and ) Under Phytohormone Stress.

The gibberellin-dioxygenase (GAox) gene family plays a crucial role in regulating plant growth and development. GAoxs, which are encoded by many gene subfamilies, are extremely critical in regulating bioactive GA levels by catalyzing the subsequent stages in the biosynthesis process. Moreover, GAoxs are important enzymes in the GA synthesis pathway, and the GAox gene family has not yet been identified in Rosaceae species ( L., , and ), especially in response to gibberellin and PCa (prohexadione calcium; reduce biologically active GAs). In the current investigation, 399 GAox members were identified in sweet cherry, Japanese apricot, and strawberry. Moreover, they were further classified into six (A-F) subgroups based on phylogeny. According to motif analysis and gene structure, the majority of the genes have a remarkably well-maintained exon-intron and motif arrangement within the same subgroup, which may lead to functional divergence. In the systematic investigation, genes have several duplication events, but segmental duplication occurs frequently. A calculative analysis of orthologous gene pairs in L., , and revealed that GAox genes are subjected to purifying selection during the evolutionary process, resulting in functional divergence. The analysis of -regulatory elements in the upstream region of the 140 members suggests a possible relationship between genes and specific functions of hormone response-related elements. Moreover, the genes display a variety of tissue expression patterns in diverse tissues, with most of the genes displaying tissue-specific expression patterns. Furthermore, most of the genes express significant expression in buds under phytohormonal stresses. Phytohormones stress analysis demonstrated that some of genes are responsible for maintaining the GA level in plant-like , , and . The subcellular localization of protein utilizing a tobacco transient transformation system into the tobacco epidermal cells predicted that GFP signals were mostly found in the cytoplasm. These findings will contribute to a better understanding of the GAox gene family's interaction with prohexadione calcium and GA, as well as provide a strong framework for future functional characterization of GAox genes in sweet cherry.