Global transcript profiling of primary stems from Arabidopsis thaliana identifies candidate genes for missing links in lignin biosynthesis and transcriptional regulators of fiber differentiation.
Different stages of vascular and interfascicular fiber differentiation can be identified along the axis of bolting stems in Arabidopsis. To gain insights into the metabolic, developmental, and regulatory events that control this pattern, we applied global transcript profiling employing an Arabidopsis full-genome longmer microarray. More than 5000 genes were differentially expressed, among which more than 3000 changed more than twofold, and were placed into eight expression clusters based on polynomial regression models. Within these, 182 upregulated transcription factors represent candidate regulators of fiber development. A subset of these candidates has been associated with fiber development and/or secondary wall formation and lignification in the literature, making them targets for functional studies and comparative genomic analyses with woody plants. Analysis of differentially expressed phenylpropanoid genes identified a set known to be involved in lignin biosynthesis. These were used to anchor co-expression analyses that allowed us to identify candidate genes encoding proteins involved in monolignol transport and monolignol dehydrogenation and polymerization. Similar analyses revealed candidate genes encoding enzymes that catalyze missing links in the shikimate pathway, namely arogenate dehydrogenase and prephenate aminotransferase.
Ehlting
Jürgen
J
Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
Mattheus
Nathalie
N
Aeschliman
Dana S
DS
Li
Eryang
E
Hamberger
Britta
B
Cullis
Ian F
IF
Zhuang
Jun
J
Kaneda
Minako
M
Mansfield
Shawn D
SD
Samuels
Lacey
L
Ritland
Kermit
K
Ellis
Brian E
BE
Bohlmann
Jörg
J
Douglas
Carl J
CJ
D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D001692:Biological Transport; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D008031:Lignin / Q000096:biosynthesis*; D010649:Phenylalanine / Q000096:biosynthesis; D018547:Plant Stems / Q000254:growth & development; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic
D014157:Transcription Factors; D010649:Phenylalanine; D008031:Lignin