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Fibroblast growth factor homologous factors are intracellular signaling proteins.

ABSTRACT: Fibroblast growth factors (FGFs) mediate cell growth, differentiation, migration, and morphogenesis by binding to the extracellular domain of cell surface receptors, triggering receptor tyrosine phosphorylation and signal transduction [1-5]. FGF homologous factors (FHFs) were discovered within vertebrate DNA sequence databases by virtue of their sequence similarity to FGFs [3, 6, 7], but the mechanism of FHF action has not been reported. We show here that FHF-1 is associated with the MAP kinase (MAPK) scaffold protein Islet-Brain-2 (IB2) [8] in the brain and in specific cell lines. FHF/IB2 interaction is highly specific, as FHFs do not bind to the related scaffold protein IB1(JIP-1b) [9, 10], nor can FGF-1 bind to IB2. We further show that FHFs enable IB2 to recruit a specific MAPK in transfected cells, and our data suggest that the scaffolds IB1 and IB2 have different MAPK specificities. Hence, FHFs are intracellular components of a tissue-specific protein kinase signaling module.

SUBMITTER: Schoorlemmer J

PROVIDER: S-EPMC3216481 | biostudies-literature | 2001 May

REPOSITORIES: biostudies-literature

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Fibroblast growth factor homologous factors are intracellular signaling proteins.

Schoorlemmer J J Goldfarb M M

Current biology : CB 20010501 10

Fibroblast growth factors (FGFs) mediate cell growth, differentiation, migration, and morphogenesis by binding to the extracellular domain of cell surface receptors, triggering receptor tyrosine phosphorylation and signal transduction [1-5]. FGF homologous factors (FHFs) were discovered within vertebrate DNA sequence databases by virtue of their sequence similarity to FGFs [3, 6, 7], but the mechanism of FHF action has not been reported. We show here that FHF-1 is associated with the MAP kinase ...[more]

PMID: 11378392

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