Abstract：Abstract MYB (v-myb avian myeloblastosis viral oncogene homolog) transcription factor plays an important role in plant development and their response to various environmental stresses. In this paper, a MYB gene named BnMYB1 was isolated from ramie (Boehmeria nivea) by rapid amplification of cDNA ends (RACE) based on the analysis of expression profiling of cadmium response genes in ramie. The full length of BnMYB1 (GenBank No.: MF741318) coding sequence was 1 029 bp, which encoded 342 amino acid. BnMYB1 protein belonged to 1RMYB subfamily which had only one conserved SANT (switching-defective protein 3 (Swi3), adaptor 2 (Ada2), nuclear receptor co-repressor (N-CoR), transcription factor (TFIIB)) domain. The similarity comparison revealed that BnMYB1 shared 86%, 77%, 79%, 80% and 76% of similarity with SANT/MYB proteins of Humulus lupulus (CBY88798.1), citrus sinensis (XP_006477144.1), Vigna radiate (XP_014509497.1), Prunus mume (XP_008238436.1) and Cicer arietinum (XP_004508939.1). Phylogenetic analysis revealed that BnMYB1 was closely to HlMYB4 of Humulus lupulus. qRT-PCR analysis indicated that BnMYB1 was a constitutive gene, but the expression of BnMYB1 in leaf was significantly higher than that of in root (P＜0.05). Furthermore, BnMYB1 gene was up-regulated by Cd stress, and the expression of BnMYB1 changed along with the stress time and Cd concentration. Collectively, our data suggest that BnMYB1 is a cadmium-responsive factor and may play potential roles in the plant adaption to cadmium stress.
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