Interaction of SsSte12 and SsMcm1 proteins. (A) The specific interaction of the SsSte12 protein with SsMcm1 protein was revealed by a Y2H assay. The yeast cells were grown on SD-Leu-Trp or SD-Leu-Trp-His-Ade media with X-Gal. The yeast transformant cells with different plasmid pairs (bait + prey): 53 + T, pGBKT7-53, and pGADT7-T, which encoded two interacting proteins as the positive control (Clontech); Lam + T, pGBKT7-Lam, and pGADT7-T, served as the negative control; SsMcm1 + SsSte12, pGBKT7-SsMcm1, and pGADT7-SsSte12; SsMcm1 + AD, pGBKT7-SsMcm1, and pGADT7; SsSte12 + SsMcm1, pGBKT7-SsSte12, and pGADT7-SsMcm1; SsSte12 + AD, pGBKT7-SsSte12, and pGADT7. (B) BiFC demonstrated the interaction of the SsSte12 protein with SsMcm1 protein. BiFC signal was also clearly detected in the nucleus. Images were captured under a fluorescence microscope 14 h after transient expression in Arabidopsis protoplast. Scale bars = 10 μm. (C) qRT-PCR of SsMcm1 expression level response in wild-type and SsSte12-silenced mutants. The constitutively expressed gene, Actin, was used as an internal control. Values are the means ± SD (n = 3; ns, no significant differences; one-way ANOVA).