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Updated: Jan 8, 2026

An Assay for Quantifying Protein-RNA Binding in Bacteria

An Assay for Quantifying Protein-RNA Binding in Bacteria

Published on: June 12, 2019

非対称イソペプチド結合が正二十面体ウイルスのゲノムRNAの方向性のある流出を誘導する

Sean M Braet¹, Varun Venkatakrishnan¹, Ranita Ramesh²

¹Department of Chemistry, Penn State University, University Park, PA 16802, USA.

Science advances

|December 12, 2025

Abstract:

Icosahedral RNA viruses rely upon essential asymmetries for directional genome egress into the host cell. How these asymmetric egress points are built into the quaternary assembly of the virion is unknown. Here, we capture the structure and dynamics of a partially expanded virus disassembly intermediate, poised to release its spring-loaded genomic RNA. The structure shows highly localized density of RNA underneath surface fivefold axes on one-half of the viral particle. This polarity in RNA distribution is associated with a unique interchain isopeptide bond (glutamic acid-lysine), which flanks conserved high-affinity RNA binding sites. This singular isopeptide bond at the asymmetric egress site confers an essential "loaded-die" feature that is critical for steering genomic RNA egress into the host cell for virus propagation.

キーワード:

非対称イソペプチド結合ゲノムRNA流出正二十面体ウイルス構造生物学ウイルス学

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Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus

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Analysis of Group IV Viral SSHHPS Using In Vitro and In Silico Methods

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