Multiscale characterization reveals oligomerization dependent phase separation of primer-independent RNA polymerase nsp8 from SARS-CoV-2
作者：Jinxin Xu, Xin Jiang, Yulong Zhang, Yan Dong, Changli Ma, Hanqiu Jiang, Taisen Zuo, Rui Chen, Yub
關鍵字：phase separation, nsp8
論文來源：期刊
具體來源：Communications Biology 2022, 5, 925
發表時間：2022年
RNA replication and transcription machinery is an important drug target for fighting against
coronavirus. Non-structure protein nsp8 was proposed harboring primase activity. However,
the RNA primer synthesis mechanism of nsp8 is still largely unknown. Here, we purified
dimer and tetramer forms of SARS-CoV-2 nsp8. Combined with dynamic light scattering,
small-angle neutron scattering and thermo-stability analysis, we found that both dimer and
tetramer become loosened and destabilized with decreasing salt concentration, and the dimer
form is more stable than the tetramer form. Further investigation showed that nsp8 dimer
and tetramer can undergo phase separation but exhibit different phase separation behaviors.
Nsp8 dimer can form liquid-like droplets in the buffer with a low concentration of NaCl; phase
separation of nsp8 tetramer depends on the assistance of RNA. Our findings on different
phase separation behaviors of nsp8 dimer and tetramer may provide insight into the functional
studies of nsp8 in coronavirus.