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

Abstract

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 (Prunus aviumL.,F. vesca, andP. mume), 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 thePavGAoxgenes have a remarkably well-maintained exon–intron and motif arrangement within the same subgroup, which may lead to functional divergence. In the systematic investigation,PavGAoxgenes have several duplication events, but segmental duplication occurs frequently. A calculative analysis of orthologous gene pairs inPrunus aviumL.,F. vesca, andP. mumerevealed that GAox genes are subjected to purifying selection during the evolutionary process, resulting in functional divergence. The analysis ofcis-regulatory elements in the upstream region of the 140PavGAoxmembers suggests a possible relationship between genes and specific functions of hormone response-related elements. Moreover, thePavGAoxgenes display a variety of tissue expression patterns in diverse tissues, with most of thePavGAoxgenes displaying tissue-specific expression patterns. Furthermore, most of thePavGAoxgenes express significant expression in buds under phytohormonal stresses. Phytohormones stress analysis demonstrated that some ofPavGAoxgenes are responsible for maintaining the GA level in plant-likePav co4017001.1 g010.1.br,Pav sc0000024.1 g340.1.br, andPav sc0000024.1 g270.1.mk. The subcellular localization ofPavGAoxprotein 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.