Genome-wide characterization and comparative analysis of R2R3-MYB transcription factors shows the complexity of MYB-associated regulatory networks in Salvia miltiorrhiza.

Caili Li,Shanfa Lu

doi:10.1186/1471-2164-15-277

Abstract

BackgroundMYB is the largest plant transcription factor gene family playing vital roles in plant growth and development. However, it has not been systematically studied in Salvia miltiorrhiza, an economically important medicinal plant.ResultsHere we report the genome-wide identification and characterization of 110 R2R3-MYBs, the largest subfamily of MYBs in S. miltiorrhiza. The MYB domain and other motifs of SmMYBs are largely conserved with Arabidopsis AtMYBs, whereas the divergence of SmMYBs and AtMYBs also exists, suggesting the conservation and diversity of plant MYBs. SmMYBs and AtMYBs may be classified into 37 subgroups, of which 31 include proteins from S. miltiorrhiza and Arabidopsis, whereas 6 are specific to a species, indicating that the majority of MYBs play conserved roles, while others may exhibit species-specialized functions. SmMYBs are differentially expressed in various tissues of S. miltiorrhiza. The expression profiles are largely consistent with known functions of their Arabidopsis counterparts. The expression of a subset of SmMYBs is regulated by microRNAs, such as miR159, miR319, miR828 and miR858. Based on functional conservation of MYBs in a subgroup, SmMYBs potentially involved in the biosynthesis of bioactive compounds were identified.ConclusionsA total of 110 R2R3-MYBs were identified and analyzed. The results suggest the complexity of MYB-mediated regulatory networks in S. miltiorrhiza and provide a foundation for understanding the regulatory mechanism of SmMYBs.

Highlights

MYB is the largest plant transcription factor gene family playing vital roles in plant growth and development
To verify the results from computational prediction,primers were designed for PCR-amplification of full-length coding sequences (CDSs) of 110 S. miltiorrhiza R2R3-MYBs
The identification and characterization of 110 SmMYB genes provides a foundation for understanding the regulatory mechanism of MYBs in S. miltiorrhiza

Summary

Introduction

MYB is the largest plant transcription factor gene family playing vital roles in plant growth and development. It has not been systematically studied in Salvia miltiorrhiza, an economically important medicinal plant. Salvia is characterized with only two stamens connected to form a lever. It includes about 900 species and is the largest genus of the Labiatae family. S. miltiorrhiza Bunge, known as Danshen in Chinese, is an economically important medicinal plant species of the Salvia genus. It shows close phylogenetic relationships with other Asian and Mediterranean species in the Salvia genus, such as S. roborowskii and S. glutinosa [2]. Since MYBs are vital regulators in plant development and plant responses to various biotic and abiotic stresses, elucidation of MYB-associated regulatory networks may greatly help in improving the growth and defense abilities of S. miltiorrhiza through genetic engineering approaches

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Results

Conclusion