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Phase separation and stress granule association of SARS-CoV-2 Nucleocapsid protein

ABSTRACT: The current work identified the protein interactors of SARS-CoV-2 Nucleocapsid RNA binding protein (NCAP or N protein) in lung cancer A-549 cells, using a co-immunoprecipitation strategy, which is coupled with SILAC-based mass spec. A significant proportion of the identified NCAP interacting proteins included stress granule (SG) and immunoregulators. SG nucleator G3BP1 showed specific interaction wit NCAP in unstressed and oxidative- or heat-stressed cells. Following stress treatment, NCAP showed enhanced association with SGs. Recombinant NCAP exhibited in vitro liquid-liquid phase separation (LLPS)to form liquid droplets. RNA stimulated NCAP to develop droplets in vitro and SG assembly in cells, and RNase A treatment completely blocked both of these functions. An RNA intercalating mitoxantrone disrupted NCAP assembly in SGs invitro and in cells. This study provides insight into the biological processes and biophysical properties of the SARS-CoV-2 NCAP and identifies a candidate way to target this protein.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Epithelial Cell, Cell Culture

DISEASE(S): Lung Carcinoma

SUBMITTER: Syam Prakash Somasekharan

LAB HEAD: Dr. Syam Prakash Somasekharan

PROVIDER: PXD023989 | Pride | 2021-11-25

REPOSITORIES: Pride

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			Action	DRS
	20201016_Syam_Spl3.raw	Raw
	20201019_Syam_Spl1-3.xlsx	Xlsx
	20201019_Syam_Spl1-3exp.mgf	Mgf
	20201019_Syam_Spl1.raw	Raw
	20201019_Syam_Spl2.raw	Raw

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