Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-11-10
pubmed:abstractText
Plants regenerated from tissue culture often display somaclonal variation, that is, somatic and often meiotically heritable phenotypic variation that can result from both genetic and epigenetic modifications. To better understand the molecular basis of somaclonal variation, we have characterized four unique tissue culture-derived epialleles of the pericarp color1 (p1) gene of maize (Zea mays L.). The progenitor p1 allele, P1-wr, is composed of multiple head-to-tail tandemly arranged copies of the complete gene unit and specifies brick-red phlobaphene pigmentation in the cob glumes. The novel epialleles identified in progeny plants regenerated from tissue culture showed partial to complete loss of p1 function indicated by pink or colorless cob glumes. Loss of pigmentation was correlated with nearly complete loss of p1 steady-state transcripts. DNA gel-blot analysis and genomic bisulfite sequencing showed that silencing of the epialleles was associated with hypermethylation of a region in the second intron of P1-wr. Presence of Unstable factor for orange1 (Ufo1), an unlinked epigenetic modifier of p1, restored the cob glume pigmentation in the silenced alleles, and such reactivation was accompanied by hypomethylation of the p1 sequence. This observation confirmed that silencing of the epialleles is indeed due to epigenetic modifications and that the p1 epialleles were capable of functioning in the presence of the correct trans-acting factors. While the low-copy regions of the genome generally undergo hypomethylation during tissue culture, our study shows that the tandemly repeated genes are also prone to hypermethylation and epigenetic silencing.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1943-2631
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
186
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
843-55
pubmed:dateRevised
2011-11-1
pubmed:meshHeading
pubmed-meshheading:20823340-Alleles, pubmed-meshheading:20823340-DNA, Intergenic, pubmed-meshheading:20823340-DNA Methylation, pubmed-meshheading:20823340-Gene Expression Regulation, Plant, pubmed-meshheading:20823340-Gene Silencing, pubmed-meshheading:20823340-Genes, Plant, pubmed-meshheading:20823340-Genome, Plant, pubmed-meshheading:20823340-Genotype, pubmed-meshheading:20823340-Introns, pubmed-meshheading:20823340-Mutation, pubmed-meshheading:20823340-Pigmentation, pubmed-meshheading:20823340-Plant Proteins, pubmed-meshheading:20823340-Promoter Regions, Genetic, pubmed-meshheading:20823340-RNA, Messenger, pubmed-meshheading:20823340-Tissue Culture Techniques, pubmed-meshheading:20823340-Transcription Factors, pubmed-meshheading:20823340-Transcriptional Activation, pubmed-meshheading:20823340-Zea mays
pubmed:year
2010
pubmed:articleTitle
Tissue culture-induced novel epialleles of a Myb transcription factor encoded by pericarp color1 in maize.
pubmed:affiliation
Department of Agronomy, University of Wisconsin, Madison, Wisconsin 53706, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't