title: Activation of secondary cell wall biosynthesis by miR319-targeted TCP4 transcription factor.
abstract: The overexpression of miR319 in plants results in delayed senescence, and high levels of miR319-targeted TCP4 transcription factor cause premature onset of this process. However, the underlying mechanisms of this pathway remain elusive. Here, we found that miR319 overexpression results in a decrease in TCP4 abundance and secondary cell wall formation in the stem. Conversely, constitutive expression of miR319-resistant TCP4 promotes secondary cell wall formation, indicating that miR319-mediated TCP4 controls secondary cell wall formation during development. Further analysis revealed that TCP4 might directly bind the promoter of VND7 to activate its expression, which triggers the expression of a VND7 transcriptional network associated with secondary cell wall biosynthesis and programmed cell death and accelerates vessel formation. In addition, the development process gradually increased TCP4 expression. These results suggest that miR319 and its target TCP4 can act as switches that turn on secondary cell wall synthesis and programmed cell death.
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Plant Germplasm and Genomics Center, The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: Xudong
authors.initials: X
authors.lastname: Sun
authors.affiliation: College of Plant Protection, Yunnan Agriculture University, Kunming, China.
authors.forename: Chongde
authors.initials: C
authors.lastname: Wang
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Plant Germplasm and Genomics Center, The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Xiang
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Plant Germplasm and Genomics Center, The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Plant Germplasm and Genomics Center, The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: Shihai
authors.initials: S
authors.lastname: Yang
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Plant Germplasm and Genomics Center, The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: JianCan
authors.initials: J
authors.lastname: Du
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Plant Germplasm and Genomics Center, The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: Yongping
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Plant Germplasm and Genomics Center, The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.|Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
authors.forename: Yunqiang
authors.initials: Y
authors.lastname: Yang
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D008031:Lignin / Q000378:metabolism; D035683:MicroRNAs / Q000378:metabolism*; D030821:Plants, Genetically Modified; D014157:Transcription Factors / Q000378:metabolism*; D052584:Xylem / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C000595631:MIRN319 microRNA, Arabidopsis; D035683:MicroRNAs; C560908:TCP4 protein, Arabidopsis; D014157:Transcription Factors; C583237:VND7 protein, Arabidopsis; D002482:Cellulose; D008031:Lignin
keywords: 
  TCP4
  ; miR319; secondary cell wall biosynthesis; transcription factor; xylem vessel element differentiation