Bay41-4109-induced aberrant polymers of hepatitis b capsid proteins are removed via STUB1-promoted p62-mediated macroautophagy

PLoS Pathog. 2022 Jan 14;18(1):e1010204. doi: 10.1371/journal.ppat.1010204. eCollection 2022 Jan.

Abstract

The hepatitis B virus (HBV) core protein (HBc) functions in multiple steps of the viral life cycle. Heteroaryldihydropyrimidine compounds (HAPs) such as Bay41-4109 are capsid protein allosteric modulators that accelerate HBc degradation and inhibit the virion secretion of HBV, specifically by misleading HBc assembly into aberrant non-capsid polymers. However, the subsequent cellular fates of these HAP-induced aberrant non-capsid polymers are not well understood. Here, we discovered that that the chaperone-binding E3 ubiquitin ligase protein STUB1 is required for the removal of Bay41-4109-induced aberrant non-capsid polymers from HepAD38 cells. Specifically, STUB1 recruits BAG3 to transport Bay41-4109-induced aberrant non-capsid polymers to the perinuclear region of cells, thereby initiating p62-mediated macroautophagy and lysosomal degradation. We also demonstrate that elevating the STUB1 level enhances the inhibitory effect of Bay41-4109 on the production of HBeAg and HBV virions in HepAD38 cells, in HBV-infected HepG2-NTCP cells, and in HBV transgenic mice. STUB1 overexpression also facilitates the inhibition of Bay41-4109 on the cccDNA formation in de novo infection of HBV. Understanding these molecular details paves the way for applying HAPs as a potentially curative regimen (or a component of a combination treatment) for eradicating HBV from hepatocytes of chronic infection patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antiviral Agents / pharmacology*
  • Capsid Proteins / drug effects*
  • Capsid Proteins / metabolism
  • Hepatitis B / virology
  • Hepatitis B virus / drug effects*
  • Hepatitis B virus / metabolism*
  • Humans
  • Macroautophagy / drug effects
  • Mice
  • Ubiquitin-Protein Ligases / metabolism*

Substances

  • Antiviral Agents
  • Capsid Proteins
  • Ubiquitin-Protein Ligases

Grants and funding

The study was supported by the National Natural Science Foundation of China [grant number 81501755], the Excellent Young Talent Program of the Health and Planning Commission of Fujian Province [grant number 2018-ZQN-58], the Joint Funds for the Innovation of Science and Technology in Fujian Province [grant number 2016Y9039], and the Natural Science Foundation of Fujian Province [grant number 2020J01603]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.