Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2000-6-29
pubmed:abstractText
Smad family proteins are essential for transforming growth factor beta (TGF-beta) signal mediation downstream of a heteromeric complex of the type I and type II receptor serine/threonine kinases. A distant family member, Smad7, is expressed in most mammalian tissues and cells and prevents TGF-beta signaling. In this study, we examined the physiologic role of Smad7 in mediating the effects of activin, a member of the TGF-beta superfamily of peptides that functions in a number of processes, including blood-cell development. We report here that Smad7 expression is specifically absent in particular hematopoietic cells that respond to activin by differentiating into the erythroid lineage and that ectopic production of Smad7 causes mouse erythroid leukemia (F5-5) cells to become resistant to activin induction of erythroid differentiation. When coexpressed with type I activin receptor ActR-I or ActR-IB in concert with type II receptor ActR-II, Smad7 efficiently reduced an early transcriptional response mediated by ActR-I but had only a minimal effect on the response mediated by ActR-IB. In the presence of Smad7, overexpression of an activated form of ActR-IB, but not of an activated form of ActR-I, induced F5-5 cells to differentiate. These results suggest that Smad7 selectively interferes with the ActR-I pathway in activin signal transduction. The findings also indicate the existence of a novel activity of Smad7 that inhibits erythroid differentiation by blocking intracellular signaling of activin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
95
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3371-9
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:10828018-3T3 Cells, pubmed-meshheading:10828018-Activin Receptors, pubmed-meshheading:10828018-Activins, pubmed-meshheading:10828018-Animals, pubmed-meshheading:10828018-CHO Cells, pubmed-meshheading:10828018-Cell Differentiation, pubmed-meshheading:10828018-Cell Line, pubmed-meshheading:10828018-Cricetinae, pubmed-meshheading:10828018-DNA-Binding Proteins, pubmed-meshheading:10828018-HL-60 Cells, pubmed-meshheading:10828018-Humans, pubmed-meshheading:10828018-Inhibins, pubmed-meshheading:10828018-K562 Cells, pubmed-meshheading:10828018-Leukemia, Erythroblastic, Acute, pubmed-meshheading:10828018-Mice, pubmed-meshheading:10828018-Receptors, Growth Factor, pubmed-meshheading:10828018-Recombinant Proteins, pubmed-meshheading:10828018-Signal Transduction, pubmed-meshheading:10828018-Smad7 Protein, pubmed-meshheading:10828018-Trans-Activators, pubmed-meshheading:10828018-Transfection, pubmed-meshheading:10828018-Tumor Cells, Cultured
pubmed:year
2000
pubmed:articleTitle
Smad7 selectively interferes with different pathways of activin signaling and inhibits erythroid leukemia cell differentiation.
pubmed:affiliation
Department of Molecular Biology, Biomolecular Engineering Research Institute, Osaka, Japan.
pubmed:publicationType
Journal Article