Specific viral RNA drives the SARS CoV-2 nucleocapsid to phase separate

Christiane Iserman, Christine A. Roden, M. Boerneke, R. Sealfon, Grace A. McLaughlin, Irwin Jungreis, Christopher Y. Park, A. Boppana, Ethan J. Fritch, Y. Hou, C. Theesfeld, O. Troyanskaya, R. Baric, T. Sheahan, K. Weeks, A. Gladfelter

bioRxiv : the preprint server for biology, 2020

A mechanistic understanding of the SARS-CoV-2 viral replication cycle is essential to develop new therapies for the COVID-19 global health crisis. In this study, we show that the SARS-CoV-2 nucleocapsid protein (N-protein) undergoes liquid-liquid phase separation (LLPS) with the viral genome, and propose a model of viral packaging through LLPS. N-protein condenses with specific RNA sequences in the first 1000 nts (5’-End) under physiological conditions and is enhanced at human upper airway temperatures. N-protein condensates exclude non-packaged RNA sequences. We comprehensively map sites bound by N-protein in the 5’-End and find preferences for single-stranded RNA flanked by stable structured elements. Liquid-like N-protein condensates form in mammalian cells in a concentration-dependent manner and can be altered by small molecules. Condensation of N-protein is sequence and structure specific, sensitive to human body temperature, and manipulatable with small molecules thus presenting screenable processes for identifying antiviral compounds effective against SARS-CoV-2.

Cited by 30 publications.

Field of study: Chemistry

10.1101/2020.06.11.147199