tetano
Editor, Senior Moderator
Mol Cells
. 2022 Dec 31;45(12):911-922.
doi: 10.14348/molcells.2022.0130. Epub 2022 Dec 19.
Glycogen Synthase Kinase-3 Interaction Domain Enhances Phosphorylation of SARS-CoV-2 Nucleocapsid Protein
Jun Seop Yun[SUP] 1 2 [/SUP], Hyeeun Song[SUP] 1 2 [/SUP], Nam Hee Kim[SUP] 1 [/SUP], So Young Cha[SUP] 1 [/SUP], Kyu Ho Hwang[SUP] 1 [/SUP], Jae Eun Lee[SUP] 1 [/SUP], Cheol-Hee Jeong[SUP] 1 [/SUP], Sang Hyun Song[SUP] 1 [/SUP], Seonghun Kim[SUP] 1 [/SUP], Eunae Sandra Cho[SUP] 1 [/SUP], Hyun Sil Kim[SUP] 1 [/SUP], Jong In Yook[SUP] 1 [/SUP]
Affiliations
Abstract
A structural protein of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), nucleocapsid (N) protein is phosphorylated by glycogen synthase kinase (GSK)-3 on the serine/arginine (SR) rich motif located in disordered regions. Although phosphorylation by GSK-3β constitutes a critical event for viral replication, the molecular mechanism underlying N phosphorylation is not well understood. In this study, we found the putative alpha-helix L/FxxxL/AxxRL motif known as the GSK-3 interacting domain (GID), found in many endogenous GSK-3β binding proteins, such as Axins, FRATs, WWOX, and GSKIP. Indeed, N interacts with GSK-3β similarly to Axin, and Leu to Glu substitution of the GID abolished the interaction, with loss of N phosphorylation. The N phosphorylation is also required for its structural loading in a virus-like particle (VLP). Compared to other coronaviruses, N of Sarbecovirus lineage including bat RaTG13 harbors a CDK1-primed phosphorylation site and Gly-rich linker for enhanced phosphorylation by GSK-3β. Furthermore, we found that the S202R mutant found in Delta and R203K/G204R mutant found in the Omicron variant allow increased abundance and hyper-phosphorylation of N. Our observations suggest that GID and mutations for increased phosphorylation in N may have contributed to the evolution of variants.
Keywords: Axin; Delta and Omicron variants; glycogen synthase kinase-3; nucleocapsid; phosphorylation; severe acute respiratory syndrome coronavirus 2.
. 2022 Dec 31;45(12):911-922.
doi: 10.14348/molcells.2022.0130. Epub 2022 Dec 19.
Glycogen Synthase Kinase-3 Interaction Domain Enhances Phosphorylation of SARS-CoV-2 Nucleocapsid Protein
Jun Seop Yun[SUP] 1 2 [/SUP], Hyeeun Song[SUP] 1 2 [/SUP], Nam Hee Kim[SUP] 1 [/SUP], So Young Cha[SUP] 1 [/SUP], Kyu Ho Hwang[SUP] 1 [/SUP], Jae Eun Lee[SUP] 1 [/SUP], Cheol-Hee Jeong[SUP] 1 [/SUP], Sang Hyun Song[SUP] 1 [/SUP], Seonghun Kim[SUP] 1 [/SUP], Eunae Sandra Cho[SUP] 1 [/SUP], Hyun Sil Kim[SUP] 1 [/SUP], Jong In Yook[SUP] 1 [/SUP]
Affiliations
- PMID: 36572560
- DOI: 10.14348/molcells.2022.0130
Abstract
A structural protein of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), nucleocapsid (N) protein is phosphorylated by glycogen synthase kinase (GSK)-3 on the serine/arginine (SR) rich motif located in disordered regions. Although phosphorylation by GSK-3β constitutes a critical event for viral replication, the molecular mechanism underlying N phosphorylation is not well understood. In this study, we found the putative alpha-helix L/FxxxL/AxxRL motif known as the GSK-3 interacting domain (GID), found in many endogenous GSK-3β binding proteins, such as Axins, FRATs, WWOX, and GSKIP. Indeed, N interacts with GSK-3β similarly to Axin, and Leu to Glu substitution of the GID abolished the interaction, with loss of N phosphorylation. The N phosphorylation is also required for its structural loading in a virus-like particle (VLP). Compared to other coronaviruses, N of Sarbecovirus lineage including bat RaTG13 harbors a CDK1-primed phosphorylation site and Gly-rich linker for enhanced phosphorylation by GSK-3β. Furthermore, we found that the S202R mutant found in Delta and R203K/G204R mutant found in the Omicron variant allow increased abundance and hyper-phosphorylation of N. Our observations suggest that GID and mutations for increased phosphorylation in N may have contributed to the evolution of variants.
Keywords: Axin; Delta and Omicron variants; glycogen synthase kinase-3; nucleocapsid; phosphorylation; severe acute respiratory syndrome coronavirus 2.