Biology Reference
In-Depth Information
Gene
Expression and transgenic phenotype
Function and target genes
References
VND7; A. thaliana
Expressed in immature protoxylem vessels
in roots and in vascular cells in shoots.
DR displayed defects in vessel formation
in the roots. OE repressed protoxylem
vessel formation without affecting
metaxylem.
Transdifferentiates various types of
cells into xylem vessel elements.
Upregulates many genes involved in
xylem vessel differentiation such as
SW biosynthesis and programmed
cell death.
Kubo et al. (2005)
,
Yamaguchi et al.
(2008)
AtMYB26; A. thaliana
Expressed in anthers. In the KO mutant, no
secondary thickening or lignification is
seen in the anther endothecium (male
sterility). OE results in ectopic secondary
thickening.
Regulates a number of genes linked to
secondary thickening, including
irregular xylem1 (IRX1), IRX3,
IRX8 and IRX12.
Yang et al. (2007)
PtMYB4; P. taeda
Expressed in lignifying tissues. OE
presented an increase of lignin deposition
extended to cell types that do not
normally lignify such as pith and phloem.
Induces lignification. Increases
expression of C3H, CCoAOMT,
COMT, CCR, while decreases PAL.
C4H and 4CL remain unchanged.
Patzlaff et al. (2003)
EgMYB2; E. gunnii
Preferentially expressed in the SX of stem
and root. OE in tobacco plants showed
an increase in SW thickness and an
alteration of the lignin profiles.
Positive regulator of lignin biosynthesis
and secondary cell wall formation.
Binds specifically the cis-regulatory
regions of the CCR and CAD
promoters.
Goicoechea et al.
(2005)
AtMYB46; A. thaliana
Expressed in fibres and vessels in stems. DR
reduces the SW thickening of fibres and
vessels. OE activates the biosynthetic
pathways of cellulose, xylan, and lignin
and concomitantly led to ectopic SW
deposition.
Master switch for SW formation.
Direct target of SND1. OE
upregulates MYB85 and KNAT7.
Directly regulates the expression of
AtMYB43, AtMYB52, AtMYB54,
AtMYB58, AtMYB63, AtC3H and
AtKNAT7, but also induces CesA7,
CesA8, FRA8 and CCoAOMT.
Ko et al. (2009)
,
Zhong et al.
(2007)
