SR-rich motif plays a pivotal role in recombinant SARS coronavirus nucleocapsid protein multimerization.
The nucleocapsid (N) protein of SARS coronavirus (SARS-CoV) is reported to function in encapsidating the viral genomic RNA into helical nucleocapsid, and its self-association is believed to be vital in coating the viral genomic RNA. Characterization of SARS-CoV N multimerization may thereby help us better understand the coronavirus assembly. In the current work, using the yeast two-hybrid technique, an unexpected interaction between residues 1-210 and 211-290 (central region) of the SARS-CoV N protein was detected, and SPR results further revealed that the SR-rich motif (amino acids 183-197) of SARS-CoV N protein is responsible for such an interaction. Chemical cross-linking and gel-filtration analyses indicated that the residues 283-422 of the SARS-CoV N protein have multimeric ability, although the full-length N protein is prone to exist predominantly as dimers. In addition, the multimeric ability of the C-terminal domain of SARS-CoV N protein could be weakened by the SR-rich motif interaction with the central region (amino acids 211-290). All of these data suggested that the SR-rich motif of the SARS-CoV N protein might play an import role in the transformation of the SARS-CoV N protein between the dimer and multimer during its binding to its central region for self-association or dissociation. This current paper will hopefully provide some new ideas in studying SARS-CoV N multimerization.
Luo
Haibin
H
Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai 201203, China.
Ye
Fei
F
Chen
Kaixian
K
Shen
Xu
X
Jiang
Hualiang
H
D020816:Amino Acid Motifs; D002850:Chromatography, Gel; D000086462:Coronavirus Nucleocapsid Proteins; D019590:Nucleocapsid Proteins / Q000737:chemistry* / Q000235:genetics; D025941:Protein Interaction Mapping; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D045473:Severe acute respiratory syndrome-related coronavirus / Q000737:chemistry* / Q000378:metabolism; D020798:Two-Hybrid System Techniques
D000086462:Coronavirus Nucleocapsid Proteins; D019590:Nucleocapsid Proteins; D011994:Recombinant Proteins