A Genome-wide CRISPR Screen Identifies ZCCHC14 as a Host Factor Required for Hepatitis B Surface Antigen Production

Abstract

Highlights d Genome-wide CRISPR screen identifies host factors regulating HBsAg expression d ZCCHC14 and TENT4A/B stabilize HBsAg expression through RNA tailing d ZCCHC14 forms a complex with TENT4B and the HBV PRE d RG7834 inhibits the enzymatic activity of TENT4A/B within the ZCCHC14-HBV PRE complex

A genome-wide CRISPR screen identifies UFMylation and TRAMP-like complexes as host factors required for hepatitis A virus infection

“…Their cellular activities include stabilization of mRNAs for translation as well as specifying different RNA species for turnover by the exosome complex (Lubas et al, 2011; Vanácová et al, 2005; Warkocki et al, 2018). Recently, ZCCHC14 has been shown to interact with PAPD5 and PAPD7 to support HBV infection (Hyrina et al, 2019) and consistent with that we observed strong reduction of HBV RNA levels in ZCCHC14 KO cells (Figure S8A).…”

“…Lastly, a comparison with results from a CRISPR screen for hepatitis B virus (HBV), a DNA virus replicating through reverse transcription, surprisingly highlighted ZCCHC14 as a shared host dependency factor between HAV and HBV (Figure S1D) (Hyrina et al, 2019). Together, these data illustrate that the host factor requirements for HAV are largely unique compared to other picornaviruses but reveal an unexpected commonality between HAV and HBV infection.…”

“…For HBV, mechanistic studies revealed that HBV surface antigen expression requires RNA tailing by TRAMP-like complexes (Hyrina et al, 2019). As HAV has a polyadenylated genome and longer poly(A) tails can promote translation (Bergamini et al, 2000), we assessed the length distribution of HAV poly(A) tails from infected WT and KO cells by polyacrylamide gel electrophoresis but we did not observe a notable difference (Figure 4D).…”

“…Surprisingly though, PAPD5, PAPD7 and ZCCHC14 were identified as critical factors for infection with HBV, a hepatotropic DNA virus with a vastly different life cycle, using chemical and genetic screens (Hyrina et al, 2019; Mueller et al, 2019). Mechanistically, the TRAMP-like complex plays an important role in HBV surface antigen expression by poly(A) tail extension of HBV mRNAs (Hyrina et al, 2019). This highlights a remarkable convergence of two unrelated hepatitis viruses to co-opt the same cellular complex in different ways.…”

Advances in Genomics for Drug Development

“…In addition to cancer, CRISPR screens have driven target prioritization for diseases as diverse as Alzheimer’s disease [ 70 ], Huntington’s disease [ 71 ], Type II diabetes [ 72 ], mitochondrial disorders [ 73 ], and ciliopathies [ 74 ]. Of note, many candidates for host-directed therapy have been identified based on independent genome-wide CRISPR screens for the host-dependency or restriction factors of a diverse array of clinically-relevant pathogens [ 75 ], such as HCMV [ 76 ], DENV [ 77 , 78 ]), Enteroviruses [ 79 ], IAV [ 80 , 81 ], HBV [ 82 ], HIV [ 83 ], Norovirus [ 84 , 85 ], SARS-CoV-2, WNV [ 86 , 87 ]), Zika [ 78 , 88 ], Legionella [ 89 ], Salmonella [ 90 ], and Mycobacteria. Application of CRISPR screens for target discovery is primarily bottlenecked by the optimization of relevant assay models.…”