Genome-wide in silico identification and comparison of Growth Regulating Factor (GRF) genes in Cucurbitaceae family

Growth-regulating factor (GRF) genes play a regulatory role for plant growth and development. The recently available cucumber, melon and watermelon genomes provide an opportunity to conduct a comprehensive overview of the GRF gene family. In the present study, identification and analysis of the GRF gene family was conducted using bioinformatics methods. Totally, 24 potential GRF genes were identified in cucumber, melon and watermelon. Cucumber and watermelon GRF gene members were physically mapped to their corresponding chromosomes. All GRF genes contain an intron whose number ranging from 2 to 3. Phylogenetic analysis categorized the cucurbit GRF proteins into 2 distinct classes. GRF proteins of cucurbits and Arabidopsis were clustered together in a joined tree and grouped into the same cluster with high bootstrap values. WRC and QLQ motifs, specific for GRF proteins, were found in all predicted GRF proteins. Gene Ontology analysis showed that majority of the GRFs was predicted to function in response to biological regulation and binding activity. In addition, predicted GRF proteins were localized in the nucleus. These results provide information about the relationship between evolution and functional divergence in the GRF family. We assume that systematic characterization of these GRF genes will enable researcher to open new insights for further exploration into the functions of this significant gene family in Cucurbitaceae family members.