RNA-Binding Protein hnRNP D Modulates Internal Ribosome Entry Site-Dependent Translation of Hepatitis C Virus RNA

Paek, Ki Young; Kim, Chon Saeng; Park, Sung Mi; Kim, Jong Heon; Jang, Sung Key

doi:10.1128/jvi.01405-08

Cited by 75 publications

(83 citation statements)

References 50 publications

(63 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…By binding to defined genomic elements and by modulating viral protein or RNA synthesis, AUF1/hnRNPD was found to accelerate or inhibit the life cycles of various RNA viruses (Paek et al 2008;Lund et al 2012;Cathcart et al 2013;Hino et al 2013;Lin et al 2014). It is quite conceivable that the methylation-enhanced RNA restructuring activity of the AUF1 p45 isoform, which was demonstrated here to support WNV replication, may underlie several of the functions of AUF1 during the replication processes of other viruses as well.…”

Section: Discussionmentioning

confidence: 67%

Arginine methylation enhances the RNA chaperone activity of the West Nile virus host factor AUF1 p45

Friedrich

Schmidt

Schierhorn

et al. 2016

RNA

View full text Add to dashboard Cite

A prerequisite for the intracellular replication process of the Flavivirus West Nile virus (WNV) is the cyclization of the viral RNA genome, which enables the viral replicase to initiate RNA synthesis. Our earlier studies indicated that the p45 isoform of the cellular AU-rich element binding protein 1 (AUF1) has an RNA chaperone activity, which supports RNA cyclization and viral RNA synthesis by destabilizing a stem structure at the WNV RNA's 3 ′ -end. Here we show that in mammalian cells, AUF1 p45 is consistently modified by arginine methylation of its C terminus. By a combination of different experimental approaches, we can demonstrate that the methyltransferase PRMT1 is necessary and sufficient for AUF1 p45 methylation and that PRMT1 is required for efficient WNV replication. Interestingly, in comparison to the nonmethylated AUF1 p45, the methylated AUF1 p45 aDMA exhibits a significantly increased affinity to the WNV RNA termini. Further data also revealed that the RNA chaperone activity of AUF1 p45 aDMA is improved and the methylated protein stimulates viral RNA synthesis considerably more efficiently than the nonmethylated AUF1 p45. In addition to its destabilizing RNA chaperone activity, we identified an RNA annealing activity of AUF1 p45, which is not affected by methylation. Arginine methylation of AUF1 p45 thus represents a specific determinant of its RNA chaperone activity while functioning as a WNV host factor. Our data suggest that the methylation modifies the conformation of AUF1 p45 and in this way affects its RNA binding and restructuring activities.

show abstract

Section: Discussionmentioning

confidence: 67%

Arginine methylation enhances the RNA chaperone activity of the West Nile virus host factor AUF1 p45

Friedrich

Schmidt

Schierhorn

et al. 2016

RNA

View full text Add to dashboard Cite

show abstract

“…La and PCBP2 proteins have been shown to interact with both of the UTRs and link the 5= and 3= ends of the viral genome, facilitating replication (22,23). Other independent studies on RNA binding proteins like hn-RNPD, hnRNPA1, HuR, Unr, hnRNPU, etc., have indicated that they interact with the viral RNA (24)(25)(26)(27). However, the molecular basis of regulation of viral replication by these RBPs remains a mystery.…”

mentioning

confidence: 99%

HuR Displaces Polypyrimidine Tract Binding Protein To Facilitate La Binding to the 3′ Untranslated Region and Enhances Hepatitis C Virus Replication

Shwetha

Kumar

Mullick

et al. 2015

J Virol

View full text Add to dashboard Cite

HuR is a ubiquitous, RNA binding protein that influences the stability and translation of several cellular mRNAs. Here, we report a novel role for HuR, as a regulator of proteins assembling at the 3= untranslated region (UTR) of viral RNA in the context of hepatitis C virus (HCV) infection. HuR relocalizes from the nucleus to the cytoplasm upon HCV infection, interacts with the viral polymerase (NS5B), and gets redistributed into compartments of viral RNA synthesis. Depletion in HuR levels leads to a significant reduction in viral RNA synthesis. We further demonstrate that the interaction of HuR with the 3= UTR of the viral RNA affects the interaction of two host proteins, La and polypyrimidine tract binding protein (PTB), at this site. HuR interacts with La and facilitates La binding to the 3= UTR, enhancing La-mediated circularization of the HCV genome and thus viral replication. In addition, it competes with PTB for association with the 3= UTR, which might stimulate viral replication. Results suggest that HuR influences the formation of a cellular/viral ribonucleoprotein complex, which is important for efficient initiation of viral RNA replication. Our study unravels a novel strategy of regulation of HCV replication through an interplay of host and viral proteins, orchestrated by HuR. IMPORTANCE Hepatitis C virus (HCV) is highly dependent on various host factors for efficient replication of the viral RNA.Here, we have shown how a host factor (HuR) migrates from the nucleus to the cytoplasm and gets recruited in the protein complex assembling at the 3= untranslated region (UTR) of HCV RNA. At the 3= UTR, it facilitates circularization of the viral genome through interaction with another host factor, La, which is critical for replication. Also, it competes with the host protein PTB, which is a negative regulator of viral replication. Results demonstrate a unique strategy of regulation of HCV replication by a host protein through alteration of its subcellular localization and interacting partners. The study has advanced our knowledge of the molecular mechanism of HCV replication and unraveled the complex interplay between the host factors and viral RNA that could be targeted for therapeutic interventions. Hepatitis C virus (HCV) was discovered in 1989 as a major cause of chronic non-A non-B hepatitis (1). HCV is an enveloped positive-strand RNA virus classified in the Hepacivirus genus within the Flaviviridae family. The single-stranded uncapped 9.6-kb RNA codes for a long polyprotein of ϳ3,000 amino acids which is then processed to structural and nonstructural proteins. The RNA genome is flanked by the 5= and 3= untranslated regions (UTRs), which are essential for translation and replication of the viral RNA. The viral proteins are synthesized by internal ribosome entry site (IRES)-mediated translation. These proteins initiate extensive remodeling of the intracellular membranes to create a detergent-resistant scaffold for viral replication, termed as the "membranous web" (2). The progeny viral genomes a...

show abstract

“…Control or hnRNP Q-specific siRNA-transfected NIH 3T3 cells were treated with cycloheximide (100 g/ml) for 5 min at 37°C and then harvested. Cell extracts were subjected to sucrose gradient analysis, as previously described (9,35). Total RNA of each fraction was purified using TRI reagent (Molecular Research Center) and subjected to real-time PCR analysis for quantification.…”

Section: Methodsmentioning

confidence: 99%

Rhythmic Interaction between Period1 mRNA and hnRNP Q Leads to Circadian Time-Dependent Translation

Lee

Woo

Kim

et al. 2012

Molecular and Cellular Biology

Self Cite

View full text Add to dashboard Cite

The mouse PERIOD1 (mPER1) protein, along with other clock proteins, plays a crucial role in the maintenance of circadian rhythms. mPER1 also provides an important link between the circadian system and the cell cycle system. Here we show that the circadian expression of mPER1 is regulated by rhythmic translational control of mPer1 mRNA together with transcriptional modulation. This time-dependent translation was controlled by an internal ribosomal entry site (IRES) element in the 5= untranslated region (5=-UTR) of mPer1 mRNA along with the trans-acting factor mouse heterogeneous nuclear ribonucleoprotein Q (mhnRNP Q). Knockdown of mhnRNP Q caused a decrease in mPER1 levels and a slight delay in mPER1 expression without changing mRNA levels. The rate of IRES-mediated translation exhibits phase-dependent characteristics through rhythmic interactions between mPer1 mRNA and mhnRNP Q. Here, we demonstrate 5=-UTR-mediated rhythmic mPer1 translation and provide evidence for posttranscriptional regulation of the circadian rhythmicity of core clock genes.

show abstract

RNA-Binding Protein hnRNP D Modulates Internal Ribosome Entry Site-Dependent Translation of Hepatitis C Virus RNA

Cited by 75 publications

References 50 publications

Arginine methylation enhances the RNA chaperone activity of the West Nile virus host factor AUF1 p45

Arginine methylation enhances the RNA chaperone activity of the West Nile virus host factor AUF1 p45

HuR Displaces Polypyrimidine Tract Binding Protein To Facilitate La Binding to the 3′ Untranslated Region and Enhances Hepatitis C Virus Replication

Rhythmic Interaction between Period1 mRNA and hnRNP Q Leads to Circadian Time-Dependent Translation

Contact Info

Product

Resources

About