Cell adhesion promoting peptide GVKGDKGNPGWPGAP from the collagen type IV triple helix: cis/trans proline-induced multiple proton NMR conformations and evidence for a KG/PG multiple turn repeat motif in the all-trans proline state

Abstract

Peptide GVKGDKGNPGWPGAPY (called peptide IV-H1), derived from the protein sequence of human collagen type IV, triple-helix domain residues 1263-1277, represents an RGD-independent, cell-specific, adhesion, spreading, and motility promoting domain in type IV collagen. In this study, peptide IV-H1 has been investigated by 1H NMR (500 MHz) spectroscopy. Cis-trans proline isomerization at each of the three proline residues gives rise to a number of slowly exchanging (500-MHz NMR time scale) conformation states. At least five such states are observed, for example, for the well-resolved A14 beta H3 group, and K3, which is six residues sequentially removed from the nearest proline, i.e., P9, shows two sets. The presence of more than two sets of resonances for residues sequentially proximal to a proline, e.g., A14-cis-P15 and A14-trans-P15, and more than one set for a residue sequentially well-removed from a proline, e.g., K3, indicates long range conformation interactions and the presence of preferred structure in this short linear peptide. Many resonances belonging to these multiple species have been assigned by using mono-proline-substituted analogues. Conformational (isomer) state-specific 2D 1H NMR assignments for the combination of cis and trans proline states have been made via analysis of COSY-type, HOHAHA, and NOESY spectra. Peptide IV-H1 in the all-trans proline state ttt exists in relatively well-defined conformation populations showing numerous short- and long-range NOEs and long-lived backbone amide protons and reduced backbone NH temperature coefficients, suggesting hydrogen-bonding, and structurally informative 3J alpha N coupling constants. The NMR data indicate significant beta-turn populations centered at K3-G4, K5-G6, P9-G10, and P12-G13, and a C-terminal gamma-turn within the A14-P15-Y16 sequence. These NMR data are supported by circular dichroic studies which indicate the presence of 52% beta-turn, 10% helix, and 38% random coil structural populations. Since equally spaced KG and PG residues are found on both sides of peptide IV-H1 in the native collagen type IV sequence, this multiple turn repeat motif may continue through a longer segment of the protein. Synthetic peptide IV-H1 overlapping sequence "walk throughs" indicate that the primary biological activity is localized in the GNPGWPGAP double beta-turn domain, which contains the backbone constraining proline residues. This proline-domain conformation may suggest a collagen type IV receptor-specific, metastatic cell adhesion promoting binding domain.

Melanoma Cell CD44 Interaction with the α1(IV)1263–1277 Region from Basement Membrane Collagen Is Modulated by Ligand Glycosylation

“…In addition to the integrin binding sites, the ␣1(IV)1263-1277 region from type IV collagen (gene-derived sequence GlyVal-Lys-Gly-Asp-Lys-Gly-Asn-Pro-Gly-Trp-Pro-Gly-Ala-Pro, designated IV-H1), promotes melanoma cell adhesion, spreading, and signaling (1,3,(12)(13)(14). Affinity chromatography studies with a single-stranded IV-H1 peptide resulted in the isolation of melanoma cell CD44 receptors, in the chondroitin sulfate proteoglycan (CSPG) form (15,16).…”

A Peptide Model of Basement Membrane Collagen α 1(IV) 531- 543 Binds the α3β1 Integrin

“…Peptide models of the ␣1(IV)1263-1277 region promote the adhesion, spreading, and migration of highly metastatic tumor cells (Chelberg et al, 1990;Mayo et al, 1991;Fields et al, 1993). A peptide incorporating the ␣1(IV)531-543 1 (Gly-Glu-Phe-Tyr-Phe-Asp-Leu-Arg-Leu-Lys-Gly-Asp-Lys-Tyr) sequence promotes keratinocyte, corneal epithelial, melanoma, ovarian carcinoma, and Jurkat cell adhesion (Wilke and Furcht, 1990;Cameron et al, 1991;Miles et al, 1994) and migration of corneal epithelial cells and keratinocytes (Cameron et al, 1991;Kim et al, 1994).…”

Localisation of a receptor‐recognition domain on the S3 subunit of pertussis toxin by peptide mapping

“…Interestingly, both PT and type-IV collagen have been found to recognise a common glycoprotein, laminin (Mayo et al, 1991;Witvliet et al, 1989). The conformation in solution for the collagen-derived peptide, and for peptides containing the fibronectin recognition sequence Arg-Gly-Asp, appears to consist of consecutive or nested p-turn structures (Mayo et al, 1991;Reed et al, 1988).…”

“…Interestingly, both PT and type-IV collagen have been found to recognise a common glycoprotein, laminin (Mayo et al, 1991;Witvliet et al, 1989). The conformation in solution for the collagen-derived peptide, and for peptides containing the fibronectin recognition sequence Arg-Gly-Asp, appears to consist of consecutive or nested p-turn structures (Mayo et al, 1991;Reed et al, 1988). For peptide (E)S3c, the ability of antibodies raised against the peptide to also recognise the holotoxin, is consistent with a putative p-turn conformation (Krchnak et al, 1989;Westhof et al, 1984).…”