CmFUL1 was potentially involved in fruit elongation in melon

Abstract

Melon (Cucumis melo L.) is a fruit crop in the world; fruit size and fruit shape are major traits for melon quality. Fruit length is a crucial indicator affecting fruit size and shape, but few genes regulating this trait have been identified. Here, we identified the transcription factor CmFUL1 (FRUITFULL) as a candidate for regulating fruit length using genome-wide association analysis (GWAS) and phylogenetic analysis. CmFUL1 is mainly expressed during flower and ovary development by tissue-specific expression. Transcriptional analysis revealed that CmFUL1 expression levels exhibited a negative correlation with fruit length across diverse melon germplasm. Furthermore, functional characterization demonstrated that CmFUL1 acts as a negative regulator of fruit elongation, CR-Cmful1 mutants generated by CRISPR-Cas9 showing enhanced longitudinal fruits. This repressive role was evolutionarily conserved, as heterologous overexpression of CmFUL1 in tomato consistently inhibited fruit elongation. Collectively, the results suggested that CmFUL1 is a candidate gene involved in regulating fruit length in melon, and provided genetic resources for molecular breeding of melon.

Acknowledgements

This research was funded by National Natural Science Foundation of China (32172581), Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2025-ZFRI), Agriculture Research System of China (CARS-25-2025-G6), the Henan Special Funds for Major Science and Technology (2211001T10400), Henan Province Science and Technology Research Project (252102110298), and International Cooperation projects of Henan Province of Science and Technology (242102520045).

Author contributions

L.T. and G.Z.: Planned and designed the research. L.T.: Analyzed the data, prepared the figures, and wrote the original draft. L.A.: Constructed the vector for transformation. M. L.: Collected data. B.L.: Took the picture of overexpressed materials and conducted the qRT-PCR assay. Y.H.: Performed the material collection. J.Z., W.K., and K.H.: Conducted fieldwork. Y.X., G.Z., and L.T.: Acquired funding. G.Z., J.G., and L.T.: Edited and approved the manuscript. All authors read and approved the final manuscript.

Data availability

Raw reads for RNA-Seq were downloaded from NCBI Sequence Read Archive (SRA) database (https://www.ncbi.nlm.nih.gov/sra) under accession number PRJNA803327 (https://www.ebi.ac.uk/ena/browser/view/PRJNA803327).

Conflict of interest statement

All authors declare that they have no conflict of interest.

Supplementary data

Supplementary data is available at Horticulture Research online.

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