Genome-Wide Identification and Characterization of MYB-CC Gene Factor Family in Sorghum and Their Response to Phosphate Starvation

The MYB-CC gene family is implicated in the response to phosphate deficiency in rice, wheat, and soybean. We aimed to identify the MYB-CC gene family members and predict their function in sorghum (Sorghum bicolor (L.) Moench). A systemic genome-wide analysis of the MYB-CC gene family in sorghum was performed. The mRNA expression level of SbMYB-CC genes in root tissue under low phosphate condition was detected by using qRT-PCR. A total of 17 SbMYB-CC genes were identified in the sorghum genome. Phylogenetic analysis revealed that SbMYB-CC proteins could be classified into five groups. Promoter regions in SbMYB-CC genes contained multiple cis-acting elements related to light response, hormone regulation, and stress response. Phylogenetic and collinearity analyses revealed MYB-CC proteins to be conserved among sorghum, rice, and maize; the SbMYB-CC gene family experienced strong purifying selection during evolution. Based on the transcriptome data, results revealed that SbMYB-CC genes presented different expression patterns in each tissue and these genes had obvious spatiotemporal expression characteristics. QRT-PCR assays showed that the expression level of SbMYB-CC1 was significantly increased under low phosphorus stress; the mRNA expression level of SbMYB-CC3, SbMYB-CC4, SbMYB-CC10, SbMYB-CC11, and SbMYB-CC16 were significantly decreased (P < 0.05). Genome-wide identification of the SbMYB-CC genes revealed the characterization and potential biological functions of this gene family in sorghum. This study also provides valuable information for further research on candidate SbMYB-CC genes in response to phosphate deficiency in sorghum.