NP - dimerisation domain structure

Tetramer formation

(Corbett 2020 pmid: 32654247) N2b domain forms a dimer in solution, addition of the C-terminal spacer B/N3 domain mediates formation of a homotetramer.

• 1.4A of N2b domain
• tetramer formation B/N3: the C-terminal spacer B/N3 domain mediates formation of a homotetramer. Using hydrogendeuterium exchange mass spectrometry, we find evidence that at least part of this putatively disordered domain is structured, potentially forming an α-helix that self-associates and cooperates with the N2b domain to mediate tetramer formation.
• 
• The structures of the N2b domain of SARS-CoV and several related coronaviruses confirmed the obligate homodimeric structure of this domain,34–40 and other work showed that the region C-terminal to this domain mediates further selfassociation into tetramer, hexamer, and potentially higher oligomeric forms.41–43 Other studies have suggested that the protein's N-terminal region, including the RNA-binding N1b domain, can also self-associate,44,45

Dimer formation

(Corbett 2020 pmid: 32654247) 270–370 shows a core stabilized by multiple hydrophobic interactions

(pmid: 32587966)

​

Dimer structure of the SARS-CoV-2 dimerization domain (PDB: 6yun). Center and left: coloured basedon surface potential, revealing the highly basic surface. Right: ribbon structure with N- and C-terminihighlighted.

(pmid: 32511359)

(Corbett 2020 pmid: 32654247) 1.4A of N2b domain; HDXMS

7-20 PDB IDs 6WJI, 6YUN, 6ZCO and 7C22; all unpublished

(PDB deposition codes 6WJI, 6WZO, 6WZQ and 7C22) - Ye Corbett, Architecture and Self-Assembly of the SARS-CoV-2 Nucleocapsid Protein, bioRxiv [Preprint], 2020, https:// doi.org/10.1101/2020.05.17.100685.

2006 SARS structure (pmid: 16627473)

dimer binds also RNA: NP CTD crystal/cryo structures

HDXMS of the dimer

(Ye Corbett 2020 Protein Sci PMID: 32654247) shows regions that are close together and not accessible