MeMYB26, a drought-responsive transcription factor in cassava (Manihot esculenta Crantz)
Bin Wang, Xin Guo, Pingjuan Zhao, Wenbin Liao, Changying Zeng, Kai Li, Yuxun Zhou, Junhua Xiao, Mengbin Ruan, Ming Peng, Yang Bai and Ye Chen
Abstract: Cassava (Manihot esculenta Crantz) is worldwide the sixth-largest food crop and highly drought resistant. The expression of the myeloblastosis (MYB) family protein MeMYB26 in cassava was previously reported to be significantly up-regulated under water deficit. To study the basic characterization, natural variations and potential functions of MeMYB26 for drought resistance in cassava, the protein was subjected to bioinformatics analysis, multiplex-PCR with next-generation sequencing and candidate association studies. The results indicated that MeMYB26 is a typical transcription factor, with two MYB DNA-binding and transcriptional activation domains. One stop-gained and five nonsynonymous variations in the genomic region of MeMYB26 were significantly
associated with drought resistance traits. The results of the scale-free coexpression network showed that the MeMYB26 gene plays a critical role in plant stress resistance, growth and biomass development. It was concluded that MeMYB26 is a reliable candidate gene associated with drought tolerance and biomass storage in cassava.