RDR1 and SGS3, components of RNA-mediated gene silencing, are required for the regulation of cuticular wax biosynthesis in developing inflorescence stems of Arabidopsis.
The cuticle is a protective layer that coats the primary aerial surfaces of land plants and mediates plant interactions with the environment. It is synthesized by epidermal cells and is composed of a cutin polyester matrix that is embedded and covered with cuticular waxes. Recently, we have discovered a novel regulatory mechanism of cuticular wax biosynthesis that involves the ECERIFERUM7 (CER7) ribonuclease, a core subunit of the exosome. We hypothesized that at the onset of wax production, the CER7 ribonuclease degrades an mRNA specifying a repressor of CER3, a wax biosynthetic gene whose protein product is required for wax formation via the decarbonylation pathway. In the absence of this repressor, CER3 is expressed, leading to wax production. To identify the putative repressor of CER3 and to unravel the mechanism of CER7-mediated regulation of wax production, we performed a screen for suppressors of the cer7 mutant. Our screen resulted in the isolation of components of the RNA-silencing machinery, RNA-DEPENDENT RNA POLYMERASE1 and SUPPRESSOR OF GENE SILENCING3, implicating RNA silencing in the control of cuticular wax deposition during inflorescence stem development in Arabidopsis (Arabidopsis thaliana).
Department of Botany, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
Patricia
P
Lam
Lifang
L
Zhao
Heather E
HE
McFarlane
Mytyl
M
Aiga
Vivian
V
Lam
Tanya S
TS
Hooker
Ljerka
L
Kunst
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D019755:Carbon-Carbon Lyases; D003001:Cloning, Molecular; D005095:Exoribonucleases / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D016153:Genes, Suppressor; D005816:Genetic Complementation Test; D056626:Inflorescence / Q000254:growth & development* / Q000378:metabolism; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D009687:Nuclear Proteins / Q000378:metabolism; D019441:Plant Epidermis / Q000378:metabolism; D018547:Plant Stems / Q000254:growth & development* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D018749:RNA, Plant / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics / Q000378:metabolism*; D019076:Transgenes; D014885:Waxes / Q000378:metabolism*
D029681:Arabidopsis Proteins; D019755:Carbon-Carbon Lyases; D005095:Exoribonucleases; D009687:Nuclear Proteins; D018749:RNA, Plant; D012324:RNA-Dependent RNA Polymerase; D014885:Waxes; C410507:SGS3 protein, Arabidopsis; C520842:CER7 protein, Arabidopsis; C103487:At5g57800 protein, Arabidopsis