TY - JOUR
T1 - Antagonistic regulation of cell-matrix adhesion by FosB and ΔFosB/Δ2ΔFosB encoded by alternatively spliced forms of fosB transcripts
AU - Ohnishi, Yoshinori N.
AU - Sakumi, Kunihiko
AU - Yamazaki, Katsuhisa
AU - Ohnishi, Yoko H.
AU - Miura, Tomofumi
AU - Tominaga, Yohei
AU - Nakabeppu, Yusaku
N1 - Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2008/11
Y1 - 2008/11
N2 - Among fos family genes encoding components of activator protein-1 complex, only the fosB gene produces two forms of mature transcripts, namely fosB and ΔfosB mRNAs, by alternative splicing of an exonic intron. The former encodes full-length FosB. The latter encodes ΔFosB and Δ2ΔFosB by alternative translation initiation, and both of these lack the C-terminal transactivation domain of FosB. We established two mutant mouse embryonic stem (ES) cell lines carrying homozygous fosB-null alleles and fosBd alleles, the latter exclusively encoding ΔFosB/Δ2ΔFosB. Comparison of their gene expression profiles with that of the wild type revealed that more than 200 genes were up-regulated, whereas 19 genes were down-regulated in a ΔFosB/Δ2ΔFosB-dependent manner. We furthermore found that mRNAs for basement membrane proteins were significantly up-regulated in fosBd/d but not fosB-null mutant cells, whereas genes involved in the TGF-β1 signaling pathway were up-regulated in both mutants. Cell-matrix adhesion was remarkably augmented in fosBd/d ES cells and to some extent in fosB-null cells. By analyzing ES cell lines carrying homozygous fosBFN alleles, which exclusively encode FosB, we confirmed that FosB negatively regulates cell-matrix adhesion and the TGF-β1 signaling pathway. We thus concluded that FosB and ΔFosB/Δ2ΔFosB use this pathway to antagonistically regulate cell matrix adhesion.
AB - Among fos family genes encoding components of activator protein-1 complex, only the fosB gene produces two forms of mature transcripts, namely fosB and ΔfosB mRNAs, by alternative splicing of an exonic intron. The former encodes full-length FosB. The latter encodes ΔFosB and Δ2ΔFosB by alternative translation initiation, and both of these lack the C-terminal transactivation domain of FosB. We established two mutant mouse embryonic stem (ES) cell lines carrying homozygous fosB-null alleles and fosBd alleles, the latter exclusively encoding ΔFosB/Δ2ΔFosB. Comparison of their gene expression profiles with that of the wild type revealed that more than 200 genes were up-regulated, whereas 19 genes were down-regulated in a ΔFosB/Δ2ΔFosB-dependent manner. We furthermore found that mRNAs for basement membrane proteins were significantly up-regulated in fosBd/d but not fosB-null mutant cells, whereas genes involved in the TGF-β1 signaling pathway were up-regulated in both mutants. Cell-matrix adhesion was remarkably augmented in fosBd/d ES cells and to some extent in fosB-null cells. By analyzing ES cell lines carrying homozygous fosBFN alleles, which exclusively encode FosB, we confirmed that FosB negatively regulates cell-matrix adhesion and the TGF-β1 signaling pathway. We thus concluded that FosB and ΔFosB/Δ2ΔFosB use this pathway to antagonistically regulate cell matrix adhesion.
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U2 - 10.1091/mbc.E07-08-0768
DO - 10.1091/mbc.E07-08-0768
M3 - Article
C2 - 18753407
AN - SCOPUS:58149277722
VL - 19
SP - 4717
EP - 4729
JO - Molecular Biology of the Cell
JF - Molecular Biology of the Cell
SN - 1059-1524
IS - 11
ER -