Spike protein of the SARS-CoV-2 omicron variant interacts with actin

Abstract

The omicron variant of SARS-CoV-2 is responsible for the COVID-19 pandemic, serving as a significant origin for the variants still being detected today. It affects the spike protein that most vaccines used to target when the Omicron strain was discovered. Here, we demonstrate that the receptor binding domain (RBD) of the Omicron variant of SARS-CoV-2 exhibits an increased affinity for human angiotensin-converting enzyme type 2 (hACE2) as a viral cell receptor compared to the prototype RBD. We also identified that {beta}- and {gamma}-actin are Omicron-specific binding partners of RBD. Protein complex predictions suggested that many of the Omicron-specific amino acid substitutions might be involved in the affinity of RBD and actin. Accordingly, we highlight the intriguing observation that proteins expected to localize to different cellular compartments exhibit strong binding.