Soybean CCA1-like MYB transcription factor GmMYB133 modulates isoflavonoid biosynthesis

• Published in: Biochemical and biophysical research communications Vol. 507; no. 1-4; pp. 324 - 329
• Main Authors: Bian, Shaomin, Li, Ruihua, Xia, Siqi, Liu, Yajing, Jin, Donghao, Xie, Xin, Dhaubhadel, Sangeeta, Zhai, Lulu, Wang, Jingying, Li, Xuyan
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 09-12-2018
• Subjects: 60 APPLIED LIFE SCIENCES; BIOSYNTHESIS; Biosynthetic Pathways; CCA1-like protein; Gene Expression Regulation, Plant; Glycine max - embryology; Glycine max - genetics; Glycine max - metabolism; GmMYB133; Isoflavones - biosynthesis; Isoflavonoids; Phylogeny; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Roots - metabolism; Protein Interaction Maps; Soybean; SOYBEANS; TRANSCRIPTION FACTORS; Transcription Factors - metabolism; CCA1-like protein; Isoflavonoids; Soybean; GmMYB133
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2018.11.033

MYB transcription factors play important roles in the regulation of phenylpropanoid biosynthesis. However, the knowledge regarding the roles of CCA1-like MYBs in phenylpropanoid pathway is limited in plants. Previously, we identified 54 CCA1-like proteins in soybean. In the study, a CCA1-like MYB (GmMYB133) was functionally characterized as a positive regulator in isoflavonoid synthesis. GmMYB133 encodes a 330 aa protein featured with one CCA1 conserved motif. Further analysis indicated that the expression pattern of GmMYB133 was near-perfectly correlated with isoflavonoid accumulation as soybean embryos develop. GmMYB133 over-expression promoted the expression of two key isoflavonoid biosynthetic genes (GmCHS8 and GmIFS2) and increased total isoflavonoid content in hairy roots. Protein-protein interaction assays indicated that GmMYB133 might form hetero- and homodimers with an isoflavonoid regulator GmMYB176 and itself, respectively, while the subcellular localization of GmMYB133 can be altered by its interaction with 14-3-3 protein. These findings provided new insights into the functional roles of CCA1-like MYB proteins in the regulation of phenylpropanoid pathway, and will contribute to the future genetic engineering in the improvement of soybean seed quality.
•A CCA1-like GmMYB133 was functionally characterized as a new positive regulator in isoflavonoid synthesis.•GmMYB133 might form hetero- and homodimers with an isoflavonoid regulator GmMYB176 and itself, respectively.•The subcellular localization of GmMYB133 can be altered by its interaction with 14-3-3 protein.