MicroRNA857 Is Involved in the Regulation of Secondary Growth of Vascular Tissues in Arabidopsis.
MicroRNAs (miRNAs) are endogenous small RNAs that repress target gene expression posttranscriptionally, and are critically involved in various developmental processes and responses to environmental stresses in eukaryotes. MiRNA857 is not widely distributed in plants and is encoded by a single gene, AtMIR857, in Arabidopsis (Arabidopsis thaliana). The functions of miR857 and its mechanisms in regulating plant growth and development are still unclear. Here, by means of genetic analysis coupled with cytological studies, we investigated the expression pattern and regulation mechanism of miR857 and its biological functions in Arabidopsis development. We found that miR857 regulates its target gene, Arabidopsis LACCASE7, at the transcriptional level, thereby reducing laccase activity. Using stimulated Raman scattering and x-ray microtomography three-dimensional analyses, we showed that miR857 was involved in the regulation of lignin content and consequently morphogenesis of the secondary xylem. In addition, miR857 was activated by SQUAMOSA PROMOTER BINDING PROTEIN-LIKE7 in response to low copper conditions. Collectively, these findings demonstrate the role of miR857 in the regulation of secondary growth of vascular tissues in Arabidopsis and reveal a unique control mechanism for secondary growth based on the miR857 expression in response to copper deficiency.
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Yuanyuan
Y
Zhao
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Sen
S
Lin
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Zongbo
Z
Qiu
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Dechang
D
Cao
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Jialong
J
Wen
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Xin
X
Deng
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Xiaohua
X
Wang
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.).
Jinxing
J
Lin
Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology (Y.Z., D.C., J.L., X.L.), and Beijing Key Laboratory of Lignocellulosic Chemistry (J.W.), Beijing Forestry University, Beijing 100083, China;Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China (S.L., Z.Q., X.D., X.W.); andUniversity of Chinese Academy of Sciences, Beijing 100049, China (S.L.) lixj@bjfu.edu.cn.
Xiaojuan
X
Li
D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D008031:Lignin / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics*; D058526:Plant Vascular Bundle / Q000235:genetics* / Q000254:growth & development; D011401:Promoter Regions, Genetic / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D036226:Seedlings / Q000166:cytology / Q000235:genetics / Q000254:growth & development; D055114:X-Ray Microtomography; D052584:Xylem / Q000166:cytology / Q000235:genetics / Q000254:growth & development
D029681:Arabidopsis Proteins; C000610746:MIRN857 microRNA, Arabidopsis; D035683:MicroRNAs; D018749:RNA, Plant; D008031:Lignin