| First Author | Castronovo V | Year | 1991 |
| Journal | J Biol Chem | Volume | 266 |
| Issue | 30 | Pages | 20440-6 |
| PubMed ID | 1834645 | Mgi Jnum | J:41058 |
| Mgi Id | MGI:892796 | Doi | 10.1016/s0021-9258(18)54943-7 |
| Citation | Castronovo V, et al. (1991) Functional domains of the 67-kDa laminin receptor precursor. J Biol Chem 266(30):20440-6 |
| abstractText | We report the characterization of two functional domains of the metastasis-associated 67-kDa laminin receptor (67-LR). Using synthetic peptides deduced from the cDNA sequence of the 37-kDa precursor of the laminin receptor (37-LRP) as well as their corresponding affinity-purified polyclonal antibodies, we identified a unique laminin binding site as well as a membrane-associated domain of the receptor. In laminin dot blot and solid phase radioligand assays, a 20 amino acid synthetic peptide (IPCNNKGAHSVGLMWWMLAR, amino acid residues 161-180, designated peptide G) specifically bound to laminin with high affinity (Kd = 5 x 10(-8) M). Peptide G also specifically eluted the 67-LR from a laminin affinity column. Peptide G and laminin reacted with a 1:1 stoichiometry, suggesting that there is one recognition site on laminin for the peptide G domain. Immunofluorescence studies, performed on permeabilized and nonpermeabilized human A2058 melanoma cells using 10 different affinity-purified antibodies to distinct regions of the 37-LRP, identified an unusually short membrane-associated domain that was consistent with a computer predicted transmembrane domain (residues 86-101). Our data demonstrate for the first time that the 37-LRP has two functional domains consistent with the characteristics of the mature 67-LR. Furthermore, we propose peptide G as a potential inhibitor of tumor cell interactions with laminin. |
