Chimeric repressor of PtSND2 severely affects wood formation in transgenic Populus.
NAC domain transcription factors are important regulators that activate the secondary wall biosynthesis in wood formation. In this work, we investigated the possible functions of an NAC family member SECONDARY WALL-ASSOCIATED NAC DOMAIN PROTEIN2 (PtSND2) using chimeric repressor silencing technology. Reverse transcription-polymerase chain reaction, subcellular localization and transcriptional activation analyses indicated that PtSND2 is a wood-associated transcriptional factor with the predicted transcriptional activation activity, which could be inhibited by the repression domain SUPERMAN REPRESSION DOMAIN X (SRDX) in yeast. Wood formation was severely repressed in transgenic poplar plants overexpressing PtSND2-SRDX. Meanwhile, the secondary cell wall thickness of xylem fibers was restrained, and the contents of cellulose and lignin were obviously decreased in the stems of transgenic plants. Further studies indicated that expressions of a number of wood-associated genes were down-regulated in the stems of transgenic plants. Our results suggest that PtSND2 may play important roles during the secondary growth of stems in poplar.
National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
H H
HH
Wang
R J
RJ
Tang
H
H
Liu
H Y
HY
Chen
J Y
JY
Liu
X N
XN
Jiang
H X
HX
Zhang
D002473:Cell Wall / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism; D015536:Down-Regulation; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D008031:Lignin / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018547:Plant Stems / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified; D032107:Populus / Q000166:cytology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation; D014934:Wood / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D052584:Xylem / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D002482:Cellulose; D008031:Lignin
PtSND2; chimeric repressor; poplar; secondary growth; transgenic plant