A truncated RHAMM protein for discovering novel therapeutic peptides

• Published in: Bioorganic & medicinal chemistry 2018-10, Vol.26 (18), p.5194-5203
• Main Authors: Hauser-Kawaguchi, Alexandra, Tolg, Cornelia, Peart, Teresa, Milne, Mark, Turley, Eva A., Luyt, Leonard G.
• Format: Article
• Language: English
• Subjects: Cell adhesion; Cell Line; Dose-Response Relationship, Drug; Extracellular Matrix Proteins - antagonists & inhibitors; Extracellular Matrix Proteins - metabolism; Humans; Hyaluronan; Hyaluronan Receptors - antagonists & inhibitors; Hyaluronan Receptors - metabolism; Kinetic evaluation; Molecular Structure; Peptide-based therapeutic agent; Peptides - chemical synthesis; Peptides - chemistry; Peptides - pharmacology; Protein-polysaccharide interaction; Pseudoproline; RHAMM; SPR; Structure-Activity Relationship
• ISSN: 0968-0896; 1464-3391
• DOI: 10.1016/j.bmc.2018.09.018

[Display omitted] •7 kDa RHAMM is a chemically synthesized, truncated receptor of native 95 kDa RHAMM.•7 kDa RHAMM is biologically active and can be synthesized in high purity.•This receptor binds hyaluronan and tubulin-derived peptides with nanomolar affinity. The receptor for hyaluronan mediated motility (RHAMM, gene name HMMR) belongs to a group of proteins that bind to hyaluronan (HA), a high-molecular weight anionic polysaccharide that has pro-angiogenic and inflammatory properties when fragmented. We propose to use a chemically synthesized, truncated version of the protein (706–767), 7 kDa RHAMM, as a target receptor in the screening of novel peptide-based therapeutic agents. Chemical synthesis by Fmoc-based solid-phase peptide synthesis, and optimization using pseudoprolines, results in RHAMM protein of higher purity and yield than synthesis by recombinant protein production. 7 kDa RHAMM was evaluated for its secondary structure, ability to bind the native ligand, HA, and its bioactivity. This 62-amino acid polypeptide replicates the HA binding properties of both native and recombinant RHAMM protein. Furthermore, tubulin-derived HA peptide analogues that bind to recombinant RHAMM and were previously reported to compete with HA for interactions with RHAMM, bind with a similar affinity and specificity to the 7 kDa RHAMM. Therefore, in terms of its key binding properties, the 7 kDa RHAMM mini-protein is a suitable replacement for the full-length recombinant protein.