The Retrovirus Capsid Core
The retrovirus capsid core is a metastable structure that disassembles during the early phase of viral infection after membrane fusion. The core is intact and permeable to essential nucleotides during reverse transcription, but it undergoes disassembly for nuclear entry and genome integration. Increasing or decreasing the stability of the capsid core has a substantial negative impact on virus infectivity, which makes the core an attractive anti-viral target. The retrovirus capsid core also encounters a variety of virus- and organism-specific host cellular factors that promote or restrict viral replication. This review describes the structural elements fundamental to the formation and stability of the capsid core. The physical and chemical properties of the capsid core that are critical to its functional role in reverse transcription and interaction with host cellular factors are highlighted to emphasize areas of current research.
KeywordsRetrovirus Comparative Maturation Capsid Capsomer Virus-host interaction Restriction factor
This work is supported by NIH grants R01 GM098550 and R01 GM124279. We thank Dr. Juan Perilla for providing the figures that show the all-atom fitting model of CA in a HIV-1 capsid core structure.
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