HIV reprograms host m6Am RNA methylome by viral Vpr protein-mediated degradation of PCIF1

Qiong Zhang,Tariq M Rana,Wanyu Li,Gwendolyn Michelle Gonzalez,Yinsheng Wang,Hui Hui,Yuqi Kang,Shaobo Wang

doi:10.1038/s41467-021-25683-4

Abstract

N6,2′-O-dimethyladenosine (m6Am) is an abundant RNA modification located adjacent to the 5′-end of the mRNA 7-methylguanosine (m7G) cap structure. m6A methylation on 2′-O-methylated A at the 5′-ends of mRNAs is catalyzed by the methyltransferase Phosphorylated CTD Interacting Factor 1 (PCIF1). The role of m6Am and the function of PCIF1 in regulating host–pathogens interactions are unknown. Here, we investigate the dynamics and reprogramming of the host m6Am RNA methylome during HIV infection. We show that HIV infection induces a dramatic decrease in m6Am of cellular mRNAs. By using PCIF1 depleted T cells, we identify 2237 m6Am genes and 854 are affected by HIV infection. Strikingly, we find that PCIF1 methyltransferase function restricts HIV replication. Further mechanism studies show that HIV viral protein R (Vpr) interacts with PCIF1 and induces PCIF1 ubiquitination and degradation. Among the m6Am genes, we find that PCIF1 inhibits HIV infection by enhancing a transcription factor ETS1 (ETS Proto-Oncogene 1, transcription factor) stability that binds HIV promoter to regulate viral transcription. Altogether, our study discovers the role of PCIF1 in HIV–host interactions, identifies m6Am modified genes in T cells which are affected by viral infection, and reveals how HIV regulates host RNA epitranscriptomics through PCIF1 degradation.

Highlights

N6,2′-O-dimethyladenosine (m6Am) is an abundant RNA modification located adjacent to the 5′-end of the mRNA 7-methylguanosine (m7G) cap structure. m6A methylation on 2′-Omethylated A at the 5′-ends of mRNAs is catalyzed by the methyltransferase Phosphorylated CTD Interacting Factor 1 (PCIF1)
These results indicate that PCIF is degraded by the proteasome and suggest that HIV viral protein R (Vpr) is the key protein involved in PCIF1 degradation
In this study, we demonstrate the role of m6Am methyltransferase, PCIF1, as an HIV restriction factor that is dependent on the methyltransferase activity of the enzyme

Summary

Introduction

N6,2′-O-dimethyladenosine (m6Am) is an abundant RNA modification located adjacent to the 5′-end of the mRNA 7-methylguanosine (m7G) cap structure. m6A methylation on 2′-Omethylated A at the 5′-ends of mRNAs is catalyzed by the methyltransferase Phosphorylated CTD Interacting Factor 1 (PCIF1). Our study discovers the role of PCIF1 in HIV–host interactions, identifies m6Am modified genes in T cells which are affected by viral infection, and reveals how HIV regulates host RNA epitranscriptomics through PCIF1 degradation. The m6A modification is catalyzed by the RNA methyltransferase complex containing METTL3 that catalyzes the addition of a methyl group at the N6 position of adenosine which affects gene expression via regulation of RNA metabolism, function, and localization[4,5]. Another abundant RNA modification near the mRNA cap structure is dimethylated adenosine, N6,2′-O-dimethyladenosine (m6Am)[6,7]. Results m6Am modification of cellular mRNA is decreased by HIV infection and is mediated by Vpr-induced PCIF1 degradation

Methods

Findings

Conclusion