Colorectum cell-derived growth factor (CRDGF) is homologous to amphiregulin, a member of the epidermal growth factor family.
We have previously shown that an autocrine factor (CRDGF) of molecular weight 25,000 is produced by the HT29 human colon cancer cell line. Although CRDGF was shown to inhibit the binding of epidermal growth factor (EGF) to its receptor, several lines of evidence suggested that it was distinct from EGF or transforming growth factor-alpha (TGF-alpha). In order to check the possibility that CRDGF represents a new member of the EGF family, a four-step purification protocol involving acid gel filtration, cation-exchange high-performance liquid chromatography (HPLC), C18 reversed-phase HPLC and gel permeation HPLC was used to purify this protein to homogeneity. The purified material exhibited a 22 kDa molecular mass on SDS-PAGE. Partial N-terminal amino acid sequence of CRDGF showed identity to amphiregulin (AR), an EGF-related protein. Western blotting experiments using AR-specific antiserum confirmed that CRDGF and AR are identical proteins. In addition, we showed that AR, like EGF or TGF-alpha stimulated the phosphorylation of the epidermal growth factor receptor (EGF-R) on tyrosine residues. This indicates that the AR intracellular signalling pathway involves the activation of EGF-R kinase.
Culouscou
J M
JM
Bristol-Myers Squibb Pharmaceutical Research Institute, Seattle, WA 98121.
Remacle-Bonnet
M
M
Carlton
G W
GW
Plowman
G D
GD
Shoyab
M
M
D000595:Amino Acid Sequence; D066258:Amphiregulin; D000818:Animals; D015153:Blotting, Western; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D003110:Colonic Neoplasms; D066255:EGF Family of Proteins; D004591:Electrophoresis, Polyacrylamide Gel; D004815:Epidermal Growth Factor / Q000737:chemistry*; D066246:ErbB Receptors / Q000187:drug effects / Q000378:metabolism*; D006023:Glycoproteins / Q000737:chemistry*; D006133:Growth Substances / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011869:Radioligand Assay; D051381:Rats; D017386:Sequence Homology, Amino Acid; D014407:Tumor Cells, Cultured
C587848:AREG protein, human; D066258:Amphiregulin; C587850:Areg protein, rat; D066255:EGF Family of Proteins; D006023:Glycoproteins; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases