MeMYB26, a drought-responsive transcription factor in cassava (Manihot esculenta Crantz)

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.