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Matthew Woods (Western University, Canada: Barr Lab)

Interferon-induced HERC5 protein inhibits HIV-1 replication by two novel mechanisms and is evolving under positive selection. Interferon-induced HERC5 protein inhibits HIV-1 replication by two novel mechanisms and is evolving under positive selection .

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Matthew Woods (Western University, Canada: Barr Lab)

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  1. Interferon-induced HERC5 protein inhibits HIV-1 replication by two novel mechanisms and is evolving under positive selection Interferon-induced HERC5 protein inhibits HIV-1 replication by two novel mechanisms and is evolving under positive selection Matthew Woods (Western University, Canada: Barr Lab) Session Title: Restriction Factors and HIV-1 Replication 21/07/2014

  2. Interferon Inhibits HIV-1 Replication Mature Virion Release T Maturation Tetherin Budding Binding U U U T Fusion Viperin Assembly APOBEC Uncoating U Gag T T U TRIM22 T Trafficking T TRIM5α Reverse Transcription U T T Nuclear Import T Translation U OAS1/RNaseL SAMHD1 U Integration T U Nuclear Export PKR U Transcription & Splicing U U U U U U U U U U U U PKR U U U U U U ISG20

  3. Our lab is interested in characterizing and identifying novel interferon-induced proteins capable of restricting HIV-1 particle production Surveyed IFN-induced genes for potential HIV-1 restriction factor candidates and identified HERC5. Identifying new interferon induced anti-HIV-1 factors

  4. HERC5 expression is up-regulated in response to IFN and both in vitro and in vivo virus infection. By virtue of its HECT domain, HERC5 is the main cellular E3 ligase that conjugates ISG15 to specific target proteins (Proc Natl Acad Sci U S A. 2006; J Biol Chem. 2006 Feb 17;281(7):4334-8) Tang and colleagues showed that HERC5 inhibits influenza A virus replication by catalyzing the conjugation of ISG15 to the viral NS1 protein (J Immunol. 2010 May 15;184(10):5777-90). Durfee and colleagues showed that HERC5 conjugates ISG15 to the human papillomavirus (HPV) L1 capsid protein, conferring a dominant-inhibitory effect on the infectivity of HPV16 pseudoviruses (Mol Cell. 2010 Jun 11;38(5):722-32). HERC5 is a novel interferon-induced antiviral protein

  5. HERC5 is multifunctional • We previously showed that HERC5 inhibits an early step of HIV-1 Gag assembly via the modification of Gag with ISG15 (Retrovirology. 2011 Nov 17;8:95) 1. E3 ligase-dependent X ISG15

  6. HERC5 is multifunctional • We previously showed that HERC5 inhibits an early step of HIV-1 Gag assembly via the modification of Gag with ISG15 (Retrovirology. 2011 Nov 17;8:95) 1. E3 ligase-dependent X ISG15 2. E3 ligase-independent X cytoplasm HERC5 nucleus

  7. Does HERC5 restrict infectious HIV-1 production? HIV only HIV + HERC5 Cell HIV HERC5

  8. HERC5 inhibits infectious HIV-1 particle production A B

  9. Do biological levels of HERC5 reduce Gag production? 293T Cells Human MDM

  10. What is causing the decrease of Gag within the cell pellet?

  11. Is Gag degraded in the presence of HERC5?

  12. Does HERC5 interfere with the nuclear export of Gag-containing mRNA?

  13. MS2 System To Localize HIV RNA Genomes Inside Cells MS2 Stem Loops GFP HIV-1 (Stem Loop) MS2-GFP HIV-1 (Stem Loop) + MS2-GFP MS2-GFP

  14. HERC5 interferes with export of genomic RNA

  15. HIV-1 and REV Late Proteins (Ex. Gag, Env, and Genome) Early Proteins (Ex. Tat, Rev Nef) REV REV REV REV REV Unspliced Fully spliced REV Rev dependant Rev independent

  16. HERC5 interferes with export of unspliced RNA Rev independent Rev dependent Viral mRNA nuclear export

  17. HERC5 inhibits export of Rev/RRE-dependent RNA Rev/RRE-dependent Rev/RRE-independent

  18. HERC5 interferes with Rev localization

  19. Which domain is required for inhibition?

  20. RLD domain is required for the loss of Gag accumulation E3 ligase-independent

  21. Evolutionary Arms Race Between Host and Pathogen VS

  22. Neighbor-joining phylogenetic tree for progressive alignment of 13 HERC5 orthologs using COBALT

  23. Strong positive selection is operating on the first 100 amino acids of the RLD

  24. Strong positive selection is operating on the first 100 amino acids of the RLD

  25. Conclusions 1. E3 ligase-independent 2. E3 ligase-dependent X cytoplasm ISG15 nucleus HERC5 X 3. HERC5 is evolving under positive selection

  26. Acknowledgements Supervisor Dr. Stephen Barr Lab Members Jenna Kelly Sean Tom Divy Kochar Johnny Zhang Mike Ding Past Lab Members Clayton Hattlmann Jess Tong Sherry Xu Macon Coleman Collaborators Dr. Dikeakos Craig Cavanagh Dr. Haeryfar Peter Szabo Funding Agencies

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