Results
author = "Pikaard, Craig S."
Postembryonic Establishment of Megabase-Scale Gene Silencing in Nucleolar Dominance
Author(s) :
Pontes, Olga
,
Lawrence, Richard J.
,
Silva, Manuela
,
Preuss, Sasha
,
Costa-Nunes, Pedro
,
Earley, Keith
,
Neves, Nuno
Description :
Nucleolar dominance is an epigenetic phenomenon in plant and animal genetic hybrids that describes the expression of 45S ribosomal RNA genes (rRNA genes) inherited from only one progenitor due to the silencing of the other progenitor's rRNA genes. rRNA genes are tandemly arrayed at nucleolus organiz...
Repository :
Europe PubMed Central
Language(s) :
English
Mechanisms of HDA6-mediated rRNA gene silencing: suppression of intergenic Pol II transcription and differential effects on maintenance versus siRNA-directed cytosine methylation
Author(s) :
Earley, Keith W.
,
Pontvianne, Frédéric
,
Wierzbicki, Andrzej T.
,
Blevins, Todd
,
Tucker, Sarah
,
Costa-Nunes, Pedro
Description :
The Arabidopsis histone deacetylase HDA6 is required to silence transgenes, transposons, and ribosomal RNA (rRNA) genes subjected to nucleolar dominance in genetic hybrids. In nonhybrid Arabidopsis thaliana, we show that a class of 45S rRNA gene variants that is normally inactivated during developme...
Repository :
Europe PubMed Central
Language(s) :
English
Histone methyltransferases regulating rRNA gene dose and dosage control in Arabidopsis
Author(s) :
Pontvianne, Frédéric
,
Blevins, Todd
,
Chandrasekhara, Chinmayi
,
Feng, Wei
,
Stroud, Hume
,
Jacobsen, Steven E.
,
Michaels, Scott D.
Description :
While plants have thousands of nearly identical rRNA genes, not all of them are constantly transcribed. At certain developmental stages, when the cellular demand is low, rRNA gene dosage is controlled via down-regulation of a subset of the genes. Pikaard and colleagues now identify the histone H3K9 ...
Repository :
Europe PubMed Central
Language(s) :
English
Spatial and functional relationships among Pol V-associated loci, Pol IV-dependent siRNAs, and cytosine methylation in the Arabidopsis epigenome
Author(s) :
Wierzbicki, Andrzej T.
,
Cocklin, Ross
,
Mayampurath, Anoop
,
Lister, Ryan
,
Rowley, M. Jordan
,
Gregory, Brian D.
,
Ecker, Joseph R.
Description :
This study by Wierzbicki et al. identifies all potential Pol V occupancy sites in the Arabidopsis genome. They show that CHH methylation in Pol IV and Pol V mutants is not abolished, but instead is mislocalized at half of the genomic sites, indicating that Pol IV and Pol V shape the epigenome by gui...
Repository :
Europe PubMed Central
Language(s) :
English
PHYTOCHROME B and HISTONE DEACETYLASE 6 Control Light-Induced Chromatin Compaction in Arabidopsis thaliana
Author(s) :
Tessadori, Federico
,
van Zanten, Martijn
,
Pavlova, Penka
,
Clifton, Rachel
,
Pontvianne, Frédéric
,
Snoek, L. Basten
Description :
Natural genetic variation in Arabidopsis thaliana exists for many traits and often reflects acclimation to local environments. Studying natural variation has proven valuable in the characterization of phenotypic traits and, in particular, in identifying genetic factors controlling these traits. It h...
Repository :
Europe PubMed Central
Language(s) :
English
Nucleolin Is Required for DNA Methylation State and the Expression of rRNA Gene Variants in Arabidopsis thaliana
Author(s) :
Pontvianne, Frédéric
,
Abou-Ellail, Mohamed
,
Douet, Julien
,
Comella, Pascale
,
Matia, Isabel
,
Chandrasekhara, Chinmayi
Description :
In eukaryotes, 45S rRNA genes are arranged in tandem arrays in copy numbers ranging from several hundred to several thousand in plants. Although it is clear that not all copies are transcribed under normal growth conditions, the molecular basis controlling the expression of specific sets of rRNA gen...
Repository :
Europe PubMed Central
Language(s) :
English
A concerted DNA methylation/histone methylation switch regulates rDNA gene dosage control and nucleolar dominance
Author(s) :
Silva, Manuela
,
Viegas, Wanda
,
Lawrence, Richard J.
,
Early, Keith
,
Pontes, Olga
,
Chen, Z.
,
Neves, Nuno
,
Pikaard, Craig.S.
Description :
Eukaryotes regulate the effective dosage of their ribosomal RNA (rRNA) genes, expressing fewer than half of the genes at any one time. Likewise, genetic hybrids displaying nucleolar dominance transcribe rRNA genes inherited from one parent but silence the other paraental set.We show that rRNA gene d...
Repository :
Repositório da Universidade Técnica de Lisboa
Language(s) :
English