Genome-wide identified VvOFP genes family and VvOFP4 functional characterization provide insight into fruit shape in grape.

Ovate Family Proteins (OFPs) are emerging as novel transcriptional regulators of fruit shape. Despite their established role in various species, their involvement in regulating grape fruit shape remains understudied. This study encompassed a comprehensive evaluation of 16 grape OFP genes in total at the whole genome level. Phylogenetic and synteny analyses established a close relationship between grape VvOFP genes and their tomato counterparts. Expression profiling post-treatment with gibberellic acid (GA3) and thidiazuron (TDZ) revealed that certain OFP genes responded to these regulators, with VvOFP4 showing peak expression three days post-anthesis. Functional assays via overexpression of VvOFP4 in tobacco and tomato altered the morphology of both vegetative and reproductive organs, including leaves, stamens, and fruits/pods. Paraffin sections of transgenic tobacco stems and tomato fruits demonstrated that VvOFP4 overexpression modifies cell dimensions, leading to changes in organ morphology. Additionally, treatments with GA3 and TDZ similarly influenced the shape of grape pulp cells and thereby the overall fruit morphology. These findings suggest that the VvOFP4 gene plays a crucial role in fruit shape determination by modulating cell shape and presents a potential target for future grape breeding programs aimed at diversifying fruit shapes.

Genome-wide identification, expression and evolution analysis of OVATE family proteins in cotton (Gossypium spp.).

OVATE family proteins (OFPs) are plant-specific transcription factors with a conserved OVATE domain. Although OFPs have been reported to regulate many aspects of plant growth and development, little is known about their evolution, structure, and function in fiber development in cotton. In this study, 174 OFPs were identified from four species of Gossypium namely, G. hirsutum, G. barbadense, G. arboreum, and G. raimondii. These OFPs were grouped into 6 sub-families by using phylogenetic analysis, and members within the same sub-family had similar conserved motifs. Chromosomal localization revealed that OFPs are distributed in cotton genome unevenly. Gene structure analysis showed that most of OFPs were intronless. Moreover, Ka/Ks analysis exhibited that OFPs were gone through purifying selection processes during evolution. Multiple cis-acting elements were observed in promoter region of OFPs, which are responsive to light, phytohormone, biotic stresses, growth and developmental related cis-acting elements. In addition, OFPs play important role in fiber and ovule development. In conclusion, this study provides a systematic analysis of cotton OFPs and provides the foundation for further studies on biological functioning of cotton OFPs.

Genome-wide analysis of OFP gene family in pepper (Capsicum annuum L.).

Ovate family proteins (OFPs) are transcriptional inhibitors that regulate plant growth and development and play important roles in the synthesis of secondary cell walls during pollen development. This study identified the pepper OFP gene family based on the genome-wide analysis and used bioinformatics methods to provide a fundamental profile of the gene family. 74 OFP genes with typical Ovate domain were identified in cultivated pepper Zunla-1, wild pepper Chiltepin and CM334. Chromosome mapping revealed that CazOFP genes were unevenly distributed on 11 chromosomes and Chr00 in Zunla-1, CacOFP genes on 12 chromosomes in Chiltepin, and CamOFP genes on 12 chromosomes and two Scaffflods in CM334. Gene structure analysis revealed that CaOFP genes possessed 1-3 exons, and the analysis of physicochemical properties suggested that CaOFPs were hydrophilic. Many cis-acting elements were identified in the promoter region of CaOFP genes, including ABRE, ARE, Box 4, G-box, TC-rich, and TCT-motif. The expression patterns of pepper at different growth stages showed that CaOFP genes were actively involved in the growth and fruit development of pepper, and CazOFP16 and CazOFP17 were actively involved in response to multiple hormones and stress events. qRT-PCR was also used to verify the expression of CazOFP gene in two developmental stages of seven pepper varieties with different fruit shapes, and it was found that CaOFP genes may be involved in the formation of fruit type in pepper. This study provides theoretical and practical evidence for future research on the OFP gene family.