Genome-wide characterization of OFP family in soybean reveals the roles of GmOFP genes involved in plant height regulation and salinity tolerance

BACKGROUND: Ovate Family Proteins (OFPs), a class of plant-specific transcription factors, play vital roles in development and abiotic stress tolerance. However, the OFP family in soybean (Glycine max) has not been extensively studied. RESULTS: In this study, a total number of GmOFP genes were identified in soybean genome (42 members, grouped into four clades). qRT-PCR analysis of GmOFPs under GA and salt treatments revealed that GmOFP1b, GmOFP2, and GmOFP7 may be involved in plant height development and salinity response, and were therefore chosen for further study. Overexpression of GmOFP1b in Arabidopsis reduced plant height by ~ 40% and shortened siliques. Furthermore, transgenic plants expressing GmOFP1b, GmOFP2, and GmOFP7 exhibited higher survival rates under salt stress at the seedling stage. Moreover, GmOFP1b interacts with GmKNOX4 proteins, and appears to play a dual role in salt tolerance in mature plants and negatively regulates the expression of GmGA20ox to control plant height. CONCLUSIONS: Our findings offer a comprehensive genomic characterization of the OFP gene family in soybean, providing a molecular framework for elucidating the functions of these genes in plant height control and salt stress tolerance.