Genome-wide identification and expression analysis of MIKC genes in rose provide insight into their effects on flower development.

The MIKC-type gene family plays important roles in plant growth, development, and tolerance of biotic and abiotic stress, especially during floral organ differentiation. However, there have been no studies of MIKC-type genes in rose, and functional differentiation of family members has not been explored. In this study, we identified 42 MIKC-type genes in rose, classified the genes into 12 subfamilies, and constructed a phylogenetic tree. We performed expression analysis of these genes, and found that expression patterns correlated with the predicted subfamily, indicating that the features of MIKC-type genes were broadly conserved during evolution. Collinear analysis of MIKC genes among Rosaceae species confirmed the occurrence of whole genome duplications (WGD) and revealed some species-specific MIKC genes. Transcriptome analysis showed that the expression of some MIKC-type genes responded to low temperatures (4°C, 24 h) during flower organ differentiation. These conserved, duplicated, and novel expression patterns of MIKC-type genes may have facilitated the adaptation of rose to various internal and external environmental changes. The results of this study provide a theoretical basis for future functional analysis of the MIKC genes in rose and investigation of the evolutionary pattern of the MIKC gene family in the Rosaceae genome.