Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
40
pubmed:dateCreated
2003-9-29
pubmed:abstractText
Plasticity of smooth muscle alpha-actin gene expression in fibroblasts and vascular smooth muscle cells is mediated by opposing effects of transcriptional activators and repressors. Among these factors, three single-stranded DNA-binding proteins, Puralpha, Purbeta, and MSY1, have been implicated as coregulators of a cryptic 5'-enhancer module. In this study, a molecular analysis of Purbeta, the least well characterized member of this group, was conducted. Southwestern and Northwestern blotting of purified Purbeta deletion mutants using smooth muscle alpha-actin-derived probes mapped the minimal single-stranded DNA/RNA-binding domain to a conserved region spanning amino acids 37-263. Quantitative binding assays indicated that the relative affinity and specificity of Purbeta for single-stranded DNA were influenced by purine/pyrimidine content; by non-conserved regions outside amino acids 37-263; and by cell-derived proteins, specifically MSY1. When overexpressed in A7r5 vascular smooth muscle cells, Purbeta (but not Puralpha) inhibited transcription of a smooth muscle-specific mouse alpha-actin promoter transgene. Structural domains required for Purbeta repressor activity included the minimal DNA-binding region and a C-terminal domain required for stabilizing high affinity protein and nucleic acid interactions. Purbeta inhibitory activity in transfected A7r5 cells was potentiated by MSY1, but antagonized by serum response factor, reinforcing the idea that interplay among activators and repressors may account for phenotypic changes in smooth muscle alpha-actin-expressing cell types.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
38749-57
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:12874279-Actins, pubmed-meshheading:12874279-Animals, pubmed-meshheading:12874279-Blotting, Northern, pubmed-meshheading:12874279-Blotting, Southern, pubmed-meshheading:12874279-Blotting, Western, pubmed-meshheading:12874279-Cell Line, pubmed-meshheading:12874279-DNA, pubmed-meshheading:12874279-DNA, Complementary, pubmed-meshheading:12874279-DNA, Single-Stranded, pubmed-meshheading:12874279-DNA-Binding Proteins, pubmed-meshheading:12874279-Dose-Response Relationship, Drug, pubmed-meshheading:12874279-Enzyme-Linked Immunosorbent Assay, pubmed-meshheading:12874279-Escherichia coli, pubmed-meshheading:12874279-Gene Deletion, pubmed-meshheading:12874279-Genes, Reporter, pubmed-meshheading:12874279-Immunoblotting, pubmed-meshheading:12874279-Mice, pubmed-meshheading:12874279-Muscle, Smooth, Vascular, pubmed-meshheading:12874279-Mutation, pubmed-meshheading:12874279-Oligonucleotides, pubmed-meshheading:12874279-Phenotype, pubmed-meshheading:12874279-Plasmids, pubmed-meshheading:12874279-Protein Binding, pubmed-meshheading:12874279-Protein Structure, Tertiary, pubmed-meshheading:12874279-Rats, pubmed-meshheading:12874279-Recombinant Proteins, pubmed-meshheading:12874279-Serum Response Factor, pubmed-meshheading:12874279-Structure-Activity Relationship, pubmed-meshheading:12874279-Time Factors, pubmed-meshheading:12874279-Transcription, Genetic, pubmed-meshheading:12874279-Transfection, pubmed-meshheading:12874279-Transgenes
pubmed:year
2003
pubmed:articleTitle
Structure/function analysis of mouse Purbeta, a single-stranded DNA-binding repressor of vascular smooth muscle alpha-actin gene transcription.
pubmed:affiliation
Department of Medicine, University of Vermont College of Medicine, Colchester, Vermont 05446, USA. robert.kelm@uvm.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't