JmjC catalysed histone H2a N-methyl arginine demethylation and C4-arginine hydroxylation reveals importance of sequence-reactivity relationships.

2-Oxoglutarate (2OG) dependent N-methyl lysine demethylases (JmjC-KDMs) regulate eukaryotic transcription. We report studies showing that isolated forms of all human KDM4 and KDM5 JmjC enzymes catalyse demethylation of N-methylated Arg-3 of histone H2a. Unexpectedly, the results reveal that KDM4E and, less efficiently, KDM4D catalyse C-4 hydroxylation of Arg-20 of H2a on peptides, recombinant H2a, and calf histone extracts, including when the Arg-20 guanidino group is N-methylated.

Inhibition of Aurora-A/N-Myc Protein-Protein Interaction Using Peptidomimetics: Understanding the Role of Peptide Cyclization.

Using N-Myc as a starting template we showcase the systematic use of truncation and maleimide constraining to develop peptidomimetic inhibitors of the N-Myc/Aurora-A protein-protein interaction (PPI); a potential anticancer drug discovery target. The most promising of these - N-Myc - is shown to favour a more Aurora-A compliant binding ensemble in comparison to the linear wild-type sequence as observed through fluorescence anisotropy competition assays, circular dichroism (CD) and nuclear magnetic resonance (NMR) experiments. Further in silico investigation of this peptide in its Aurora-A bound state, by molecular dynamics (MD) simulations, imply (i) the bound conformation is more stable as a consequence of the constraint, which likely suppresses dissociation and (ii) the constraint may make further stabilizing interactions with the Aurora-A surface.

α-Helix stabilization by co-operative side chain charge-reinforced interactions to phosphoserine in a basic kinase-substrate motif.

How cellular functions are regulated through protein phosphorylation events that promote or inhibit protein-protein interactions (PPIs) is key to understanding regulatory molecular mechanisms. Whilst phosphorylation can orthosterically or allosterically influence protein recognition, phospho-driven changes in the conformation of recognition motifs are less well explored. We recently discovered that clathrin heavy chain recognizes phosphorylated TACC3 through a helical motif that, in the unphosphorylated protein, is disordered.

Peptide-based inhibitors of protein-protein interactions: biophysical, structural and cellular consequences of introducing a constraint.

Protein-protein interactions (PPIs) are implicated in the majority of cellular processes by enabling and regulating the function of individual proteins. Thus, PPIs represent high-value, but challenging targets for therapeutic intervention. The development of constrained peptides represents an emerging strategy to generate peptide-based PPI inhibitors, typically mediated by α-helices.

Comparison of informal caregiver and named nurse assessment of symptoms in elderly patients dying in hospital using the palliative outcome scale.

Objectives: A prospective study of symptom assessments made by a healthcare professional (HCP; named nurse) and an informal caregiver (ICG) compared with that of the patient with a terminal diagnosis. To look at the validity of HCP and ICG as proxies, which symptoms they can reliably assess, and to determine who is the better proxy between HCP and ICG.

Methods: A total of 50 triads of patient (>65 years) in the terminal phase, ICG and named nurse on medical wards of an acute general hospital.