Fig. 2

Phylogenetic analysis of RopGEF family from Oryza sativa and Arabidopsis thaliana. a The phylogenetic tree was constructed by annotating the protein sequences for each gene by using MEGA7. Protein sequence alignment was performed by ClustalW and phylogeny by Neighbor-joining methods, with the reliability being estimated by the 1000 times bootstrap test. The number between the trees represents the bootstrap value. Os, Oryza sativa; At, Arabidopsis thaliana. Red and green asterisks indicate RopGEF genes with high expression in pollen in O. sativa (in this study) and Arabidopsis thaliana [8], respectively. Red and blue boxes indicate the orthologous relation between rice and Arabidopsis RopGEF genes indicated in RGAP. b A scheme of protein structure. We arranged the sequence of the protein domain scheme to be the same as the gene sequence of the phylogenetic tree of A. Length of each RopGEF protein is shown on the right and its unit is aa (amino acid). C1, C2, and C3 (blue boxes) indicate position and length of the conserved PRONE subdomain of the RopGEF family