The nucleoprotein (N) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for genome replication, encapsidating the viral genome and regulating gene transcription. The central disordered domain is essential to the function of this highly dynamic protein, containing a number of important mutations that are responsible for enhanced viral fitness, and comprising a region that is hyperphosphorylated during the viral cycle. NMR spectroscopy is the tool of choice for studying the conformational behaviour of intrinsically disordered proteins, an abundant class of proteins that are functional in their disordered form. They represent 40% of the proteome and are too dynamic to be studied by crystallography or electron microscopy. The host lab has developed a large number of unique NMR-based tools to help understand the function of this class of proteins at atomic resolution. We will use NMR, paramagnetic NMR, small angle scattering, single molecule FRET and electron microscopy, in combination with molecular dynamics simulation, to describe the interactions of N with viral partner proteins and viral RNA. Post-translational modification, in particular phosphorylation, is thought to play an important functional role, that remains poorly understood, we will investigate the impact of phosphorylation on conformational dynamics and relate this to modifications in function. The results will be correlated with light end electron microscopy, carried out in collaboration.