1. On–Off Switches for Secondary Cell Wall Biosynthesis
Huan-Zhong Wang, Richard A. Dixon 
Molecular Plant 
Volume 5, Issue 2, Pages (March 2012)
DOI: /mp/ssr098
Copyright © 2012 The Authors. All rights reserved. Terms and Conditions

2. Figure 1
Cross-Sections of an Arabidopsis Stem Showing Different Cell Types.
Stem segments were fixed, dehydrated, and embedded in L.R. white. After sectioning, the samples were stained with toluidine blue. EP, epidermal cells; Vb, vascular bundle; IF, interfascicular fiber. Cells with secondary cell walls in the VB and IF region show a different color (blue) compared to other cell types. Pith cells bear only primary cell walls and comprise a large area of the section, which could potentially be transformed into secondary cell walls to increase biomass density.
Molecular Plant 2012 5, DOI: ( /mp/ssr098)
Copyright © 2012 The Authors. All rights reserved. Terms and Conditions

3. Figure 2 Complex Regulation of the NAC Master Switch.
(A) Simplified model showing NAC domain TF functions (modified from Demura and Ye, 2010).
(B) The NAC domain transcription factor SND1 is under both positive auto-regulation and negative regulation by its downstream MYB TFs.
Molecular Plant 2012 5, DOI: ( /mp/ssr098)
Copyright © 2012 The Authors. All rights reserved. Terms and Conditions

4. Figure 3 WRKY12 Functions via the NAC Domain Transcription Factor.
UV microscopy showing the phenotypes of (A) the wrky12-1 mutant, (B) the nst2 mutant, and (C) the wrky12-1:nst2 double mutant. The double mutant shows the same phenotype as nst2, indicating that NST2 function is epistatic to that of WRKY12.
(D) WRKY function in repression of the NAC domain transcriptional cascades and therefore secondary wall development in wild-type pith cells.
(E) Elimination of the function of WRKY12 causes de-repression of NAC domain transcription factor (NST2) pathway genes, resulting in secondary wall development in pith cells.
(F) wrky12-1:nst2 double mutant plants show normal primary wall development in pith.
Molecular Plant 2012 5, DOI: ( /mp/ssr098)
Copyright © 2012 The Authors. All rights reserved. Terms and Conditions