4HMM

Crystal structure of mutant rabbit PRP 121-230 (S174N)

Summary for 4HMM

• Entry DOI: 10.2210/pdb4hmm/pdb
• Related: 3O79 4HLS 4HMR
• Descriptor: Major prion protein, CHLORIDE ION, SODIUM ION, ... (5 entities in total)
• Functional Keywords: prp, prion, membrane, membrane protein
• Biological source: Oryctolagus cuniculus (European rabbit,Japanese white rabbit,domestic rabbit,rabbits)
• Cellular location: Cell membrane; Lipid-anchor, GPI-anchor (By similarity): Q95211
• Total number of polymer chains: 2
• Total formula weight: 30950.07

Authors

Sweeting, B.,Chakrabartty, A.,Pai, E.F. (deposition date: 2012-10-18, release date: 2013-05-15, Last modification date: 2023-09-20)

Primary citation

Sweeting, B.,Brown, E.,Khan, M.Q.,Chakrabartty, A.,Pai, E.F.
N-Terminal Helix-Cap in alpha-Helix 2 Modulates beta-State Misfolding in Rabbit and Hamster Prion Proteins.
Plos One, 8:e63047-e63047, 2013

PubMed Abstract: Susceptibility of a particular species to prion disease is affected by small differences in the sequence of PrP and correlates with the propensity of its PrP to assume the β-state. A helix-cap motif in the β2-α2-loop of native α-helical rabbit PrP, a resistant species, contains sequence differences that influence intra- and interspecies transmission. To determine the effect the helix-cap motif on β-state refolding propensity, we mutated S170N, S174N, and S170N/S174N of the rabbit PrP helix-cap to resemble that of hamster PrP and conversely, N170S, N174S, and N170S/N174S of hamster PrP to resemble the helix-cap of rabbit PrP. High-resolution crystal structures (1.45-1.6 Å) revealed that these mutations ablate hydrogen-bonding interactions within the helix-cap motif in rabbit PrP(C). They also alter the β-state-misfolding propensity of PrP; the serine mutations in hamster PrP decrease the propensity up to 35%, whereas the asparagine mutations in rabbit PrP increase it up to 42%. Rapid dilution of rabbit and hamster into β-state buffer conditions causes quick conversion to β-state monomers. Kinetic monitoring using size-exclusion chromatography showed that the monomer population decreases exponentially mirrored by an increase in an octameric species. The monomer-octamer transition rates are faster for hamster than for rabbit PrP. The N170S/N174S mutant of hamster PrP has a smaller octamer component at the endpoint compared to the wild-type, whereas the kinetics of octamer formation in mutant and wild-type rabbit PrP are comparable. These findings demonstrate that the sequence of the β2-α2 helix-cap affects refolding to the β-state and subsequently, may influence susceptibility to prion disease.

PubMed: 23675452
DOI: 10.1371/journal.pone.0063047

Experimental method

X-RAY DIFFRACTION (1.5 Å)