Abstract
The INK4 family of proteins restricts uncontrolled cell cycle progression by inhibiting cyclin-dependent kinases 4 and 6. The family consists of small, monomeric and mainly alpha-helical proteins that are conserved across all vertebrate species. We recently discovered that the human INK4 protein p16 converts into amyloid structures upon oxidation of the single cysteine residue present. Here we investigate the Danio rerio (zebrafish) orthologue P18 protein. The 170-residue protein contains two cysteines which may similarly mediate transition into amyloids upon oxidation. We present the near complete backbone assignment of the reduced P18 protein in solution. These chemical shift data provide the foundation for studying oxidation-induced structural changes and protein interactions.