tetano
Editor, Senior Moderator
J Biol Chem
. 2023 Apr 10;104697.
doi: 10.1016/j.jbc.2023.104697. Online ahead of print.
SARS-CoV-2 polyprotein substrate regulates the stepwise M[SUP]pro[/SUP] cleavage reaction
Manju Narwal[SUP] 1 [/SUP], Jean-Paul Armache[SUP] 2 [/SUP], Thomas J Edwards[SUP] 3 [/SUP], Katsuhiko S Murakami[SUP] 4 [/SUP]
Affiliations
Abstract
The processing of the Coronavirus polyproteins pp1a and pp1ab by the main protease M[SUP]pro[/SUP] to produce mature proteins is a crucial event in virus replication and a promising target for antiviral drug development. M[SUP]pro[/SUP] cleaves polyproteins in a defined order, but how M[SUP]pro[/SUP] and/or the polyproteins determine the order of cleavage remains enigmatic due to a lack of structural information about polyprotein-bound M[SUP]pro[/SUP]. Here, we present the cryo-EM structures of SARS-CoV-2 M[SUP]pro[/SUP] in an apo form and in complex with the nsp7-10 region of the pp1a polyprotein. The complex structure shows that M[SUP]pro[/SUP] interacts with only the recognition site residues between nsp9 and nsp10, without any association with the rest of the polyprotein. Comparison between the apo form and polyprotein-bound structures of M[SUP]pro[/SUP] highlights the flexible nature of the active site region of M[SUP]pro[/SUP], which allows it to accommodate 10 recognition sites found in the polyprotein. These observations suggest that the role of M[SUP]pro[/SUP] in selecting a preferred cleavage site is limited and underscore the roles of the structure, conformation and/or dynamics of the polyproteins in determining the sequence of polyprotein cleavage by M[SUP]pro[/SUP].
Keywords: 3CL main protease (M(pro)); SARS CoV-2; cryogenic electron microscopy (cryo-EM); polyprotein; proteolytic processing.
. 2023 Apr 10;104697.
doi: 10.1016/j.jbc.2023.104697. Online ahead of print.
SARS-CoV-2 polyprotein substrate regulates the stepwise M[SUP]pro[/SUP] cleavage reaction
Manju Narwal[SUP] 1 [/SUP], Jean-Paul Armache[SUP] 2 [/SUP], Thomas J Edwards[SUP] 3 [/SUP], Katsuhiko S Murakami[SUP] 4 [/SUP]
Affiliations
- PMID: 37044215
- DOI: 10.1016/j.jbc.2023.104697
Abstract
The processing of the Coronavirus polyproteins pp1a and pp1ab by the main protease M[SUP]pro[/SUP] to produce mature proteins is a crucial event in virus replication and a promising target for antiviral drug development. M[SUP]pro[/SUP] cleaves polyproteins in a defined order, but how M[SUP]pro[/SUP] and/or the polyproteins determine the order of cleavage remains enigmatic due to a lack of structural information about polyprotein-bound M[SUP]pro[/SUP]. Here, we present the cryo-EM structures of SARS-CoV-2 M[SUP]pro[/SUP] in an apo form and in complex with the nsp7-10 region of the pp1a polyprotein. The complex structure shows that M[SUP]pro[/SUP] interacts with only the recognition site residues between nsp9 and nsp10, without any association with the rest of the polyprotein. Comparison between the apo form and polyprotein-bound structures of M[SUP]pro[/SUP] highlights the flexible nature of the active site region of M[SUP]pro[/SUP], which allows it to accommodate 10 recognition sites found in the polyprotein. These observations suggest that the role of M[SUP]pro[/SUP] in selecting a preferred cleavage site is limited and underscore the roles of the structure, conformation and/or dynamics of the polyproteins in determining the sequence of polyprotein cleavage by M[SUP]pro[/SUP].
Keywords: 3CL main protease (M(pro)); SARS CoV-2; cryogenic electron microscopy (cryo-EM); polyprotein; proteolytic processing.