Regulation of secondary cell wall biosynthesis by poplar R2R3 MYB transcription factor PtrMYB152 in Arabidopsis.
Poplar has 192 annotated R2R3 MYB genes, of which only three have been shown to play a role in the regulation of secondary cell wall formation. Here we report the characterization of PtrMYB152, a poplar homolog of the Arabidopsis R2R3 MYB transcription factor AtMYB43, in the regulation of secondary cell wall biosynthesis. The expression of PtrMYB152 in secondary xylem is about 18 times of that in phloem. When expressed in Arabidopsis under the control of either 35S or PtrCesA8 promoters, PtrMYB152 increased secondary cell wall thickness, which is likely caused by increased lignification. Accordingly, elevated expression of genes encoding sets of enzymes in secondary wall biosynthesis were observed in transgenic plants expressing PtrMYB152. Arabidopsis protoplast transfection assays suggested that PtrMYB152 functions as a transcriptional activator. Taken together, our results suggest that PtrMYB152 may be part of a regulatory network activating expression of discrete sets of secondary cell wall biosynthesis genes.
1] Key Laboratory of Molecular Epigenetics of MOE & Key Laboratory of Vegetation Ecology of MOE, Northeast Normal University, Changchun, 130024, China [2] Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada [3].
Shucai
S
Wang
1] Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada [2].
Eryang
E
Li
Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
Ilga
I
Porth
1] Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada [2] Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Jin-Gui
JG
Chen
Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
Shawn D
SD
Mansfield
Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
Carl J
CJ
Douglas
D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D020570:Genes, myb / Q000235:genetics*; D007124:Immunoenzyme Techniques; D052585:Phloem / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D032107:Populus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics
D010940:Plant Proteins; D012333:RNA, Messenger; D014157:Transcription Factors