Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2011-7-13
pubmed:abstractText
Continuous treatment with parathyroid hormone (PTH) or excess endogenous PTH due to primary hyperparathyroidism causes increased bone resorption and, subsequently, decreased bone volume. Our previous studies showed that myeloid Elf-1-like factor (MEF) not only suppresses osteoblast differentiation through inhibition of Runx2 activity and other osteogenesis-related genes but also specifically increases the expression of Mab21, a potential transcriptional repressor of osteoblast differentiation. Here we show that the JNK1 pathway is involved in the MEF-mediated up-regulation of Mab21 expression due to PTH stimulation. PTH increased the transcription level of Mab21 in MG63 human osteoblastic cells, in contrast to the suppressive effect of TGF?1. PTH phosphorylates serine residues of MEF as well as c-Jun, a known substrate of JNK1. By in vitro kinase assay, we confirmed that MEF is phosphorylated by JNK1, but not by ERK. Co-transfection of MEF with both MKK4 and JNK1 increased the promoter activity of Mab21 in CV1?cells significantly more than MEF alone. We also identified the phosphorylation of MEF serine 641 by in vitro and in vivo JNK1 kinase assays combined with a proteomics approach. In conclusion, our findings indicate that MEF is involved in PTH suppression of osteoblasts through activating the MKK4/JNK1 pathway and subsequently up-regulating Mab21 expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1097-4644
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Wiley-Liss, Inc.
pubmed:issnType
Electronic
pubmed:volume
112
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2051-61
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
PTH regulates myleoid ELF-1-like factor (MEF)-induced MAB-21-like-1 (MAB21L1) expression through the JNK1 pathway.
pubmed:affiliation
Department of Biochemistry, School of Dentistry, Kyungpook National University, Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't