MiR156 regulates anthocyanin biosynthesis through SPL targets and other microRNAs in poplar

Yamei Wang; Wenwen Liu; Xinwei Wang; Ruijuan Yang; Zhenying Wu; Han Wang; Lei Wang; Zhubing Hu; Siyi Guo; Hailing Zhang; Jinxing Lin; Chunxiang Fu

doi:10.1038/s41438-020-00341-w

MiR156 regulates anthocyanin biosynthesis through SPL targets and other microRNAs in poplar

Hortic Res. 2020 Aug 1:7:118. doi: 10.1038/s41438-020-00341-w. eCollection 2020.

Authors

Yamei Wang^#^{1

2}, Wenwen Liu^#¹, Xinwei Wang³, Ruijuan Yang^{1

2}, Zhenying Wu¹, Han Wang^{1

2}, Lei Wang⁴, Zhubing Hu⁴, Siyi Guo⁴, Hailing Zhang⁵, Jinxing Lin³, Chunxiang Fu¹

Affiliations

¹ Shandong Provincial Key Laboratory of Energy Genetics, Key Laboratory of Biofuels, Chinese Academy of Sciences, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China.
² University of Chinese Academy of Sciences, Beijing, 100049 China.
³ College of Biological Sciences & Biotechnology, Beijing Forestry University, Beijing, 10083 China.
⁴ Collaborative Innovation Center of Crop Stress Biology, Henan Province and Institute of Plant Stress Biology, Henan University, Kaifeng, 475001 China.
⁵ Grass and Science Institute of Heilongjiang Academy of Agricultural Sciences, Harbin, Heilongjiang China.

^# Contributed equally.

Abstract

Anthocyanins biosynthesized from the flavonoid pathway are types of pigments that are involved in the protection of poplar from biotic and abiotic stresses. Previous researchers studying anthocyanin-related transcription factors and structural genes in poplar have made significant discoveries. However, little is known about the regulatory role of microRNAs in anthocyanin biosynthesis in poplar. Here, we overexpressed miR156 in poplar to study the comprehensive effects of the miR156-SPL module on the biosynthesis of anthocyanins. Small RNA sequencing analysis revealed 228 microRNAs differentially expressed in transgenic poplar plants with dramatically increased miR156 levels. Furthermore, integrated microRNAomic and transcriptomic analysis suggested that two microRNAs, miR160h, and miR858, have the potential to affect anthocyanin accumulation in poplar by regulating auxin response factors and MYB transcription factors, respectively. Additionally, the accumulation of miR160h and miR858 displayed a positive correlation with miR156 levels, suggesting a possible interaction between the miR156-SPL module and these microRNAs in poplar. Last, metabolomics analysis revealed that the levels of anthocyanins, flavones, and flavonols were substantially elevated in transgenic poplar plants overexpressing miR156 compared with the wild type, whereas the total lignin content was reduced in the transgenic plants. Taken together, our results indicate that miR156 can fine tune the anthocyanin biosynthetic pathway via multiple factors, including microRNAs, transcription factors, and the levels of structural genes, in poplar. This provides additional clues for understanding the complex regulatory network of anthocyanin biosynthesis in woody plants.

Keywords: Molecular engineering in plants; Secondary metabolism.