The role of mRNA 5′‐noncoding and 3′‐end sequences on 40S ribosomal subunit recruitment, and how RNA viruses successfully compete with cellular mRNAs to ensure their own protein synthesis

Kean, Katherine M.

doi:10.1016/s0248-4900(03)00030-3

Cited by 35 publications

(29 citation statements)

References 82 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Such interactions have been demonstrated for a number of systems to provide the means to fine tune the regulation of viral replication or transcription against the needs of other required processes, such as translation (14,18,20,22,28,30,44). For BMV, the 5Ј portion of RNA3 was shown to help the initiation of minus-strand RNAs at the 3Ј end of the BMV RNA (9).…”

Section: Discussionmentioning

confidence: 99%

Replicase-Binding Sites on Plus- and Minus-Strand Brome Mosaic Virus RNAs and Their Roles in RNA Replication in Plant Cells

Choi

Hema

Gopinath

et al. 2004

J Virol

View full text Add to dashboard Cite

The cis-acting elements for Brome mosaic virus (BMV) RNA synthesis have been characterized primarily for RNA3. To identify additional replicase-binding elements, nested fragments of all three of the BMV RNAs, both plus-and minus-sense fragments, were constructed and tested for binding enriched BMV replicase in a template competition assay. Ten RNA fragments containing replicase-binding sites were identified; eight were characterized further because they were more effective competitors. All eight mapped to noncoding regions of BMV RNAs, and the positions of seven localized to sequences containing previously characterized core promoter elements ( The replication of positive-strand RNA viruses is essential for pathogenesis. The responsible enzyme, the viral replicase, is a complex that includes the virus-encoded RNA-dependent RNA polymerase, additional viral replicase proteins, and host factors (6, 32). In addition, specific interactions between the viral genomic RNAs and viral replicase are required for replication and/or transcription of the viral RNAs (1, 6). The interaction process is likely to be quite complex because an RNA virus expresses different classes of RNAs at programmed levels and times.Brome mosaic virus (BMV) belongs to the alphavirus-like superfamily of plant and animal positive-strand RNA viruses. The BMV genome is divided into three capped RNAs, designated RNA1, RNA2, and RNA3 (3, 26). RNA1 and RNA2 encode replication-associated proteins, while RNA3 encodes two proteins required for systemic movement of the virus in plants and encapsidation of viral RNAs. Due to the dicistronic nature of RNA3, the second cistron encoding the capsid is translated from subgenomic RNA that is transcribed from the subgenomic promoter. In all, three classes of RNAs must be produced during successful BMV replication: genomic minusstrand, genomic plus-strand, and subgenomic RNAs.cis-acting elements for efficient genomic plus-strand, minusstrand, and subgenomic BMV RNA synthesis have been characterized by a combination of approaches, including RNA synthesis by the BMV replicase in vitro (37), transfection of BMV RNAs into protoplasts (34), analysis in plants (7), and replication in Saccharomyces cerevisiae, which is permissive for BMV replication and transcription (23). Each study generally focused on one cis-acting element and on RNA3, which does not contain functions directly required for replication. Nonetheless, a number of required elements have been identified (Fig. 1).The 3Ј noncoding regions (NCR) of BMV genomic plusstrand RNAs form a tRNA-like structure that directs the initiation of minus-strand RNA synthesis in vitro (10, 15) and in vivo (38, 46). Stem-loop C (SLC) within the tRNA-like structure of RNA3 binds the BMV replicase through an RNA structure called a clamped adenine motif (29). Given the highly similar structures predicted for RNA1 and RNA2, it is likely that the same structures are required to direct their minusstrand replication (Fig. 1). A mutation in SLC in RNA2 was shown to affect RNA replicat...

show abstract

Section: Discussionmentioning

confidence: 99%

Replicase-Binding Sites on Plus- and Minus-Strand Brome Mosaic Virus RNAs and Their Roles in RNA Replication in Plant Cells

Choi

Hema

Gopinath

et al. 2004

J Virol

View full text Add to dashboard Cite

show abstract

“…hepatitis C virus (HCV), EMCV, rhinovirus, hepatitis A virus (HAV) and HIV), and ITAFs are also implicated in these processes (for a review see Ref. 26). …”

Section: Eukaryotic Translation Initiation Factor 4gi (Eif4gi)mentioning

confidence: 99%

Translation of Eukaryotic Translation Initiation Factor 4GI (eIF4GI) Proceeds from Multiple mRNAs Containing a Novel Cap-dependent Internal Ribosome Entry Site (IRES) That Is Active during Poliovirus Infection

Byrd¹,

Zamora

Lloyd

2005

Journal of Biological Chemistry

View full text Add to dashboard Cite

Eukaryotic translation initiation factor 4GI (eIF4GI)is an essential scaffolding protein required to recruit the 43 S complex to the 5-end of mRNA during translation initiation. We have previously demonstrated that eIF4GI protein expression is translationally regulated. This regulation is mediated by cis-acting RNA elements, including an upstream open reading frame and an IRES that directs synthesis of five eIF4GI protein isoforms via alternative AUG initiation codon selection. Here, we further characterize eIF4GI IRES function and show that eIF4GI is expressed from several distinct mRNAs that vary via alternate promoter use and alternate splicing. Several mRNA variants contain the IRES element. We found that IRES activity mapped to multiple regions within the eIF4GI RNA sequence, but not within the 5-UTR per se. However, the 5-UTR enhanced IRES activity in vivo and played a role in initiation codon selection. The eIF4GI IRES was active when transfected into cells in an RNA form, and thus, does not require nuclear processing events for its function. However, IRES activity was found to be dependent upon the presence, in cis, of a 5 m 7 guanosine-cap. Despite this requirement, the eIF4GI IRES was activated by 2A protease cleavage of eIF4GI, in vitro, and retained the ability to promote translation during poliovirus-mediated inhibition of capdependent translation. These data indicate that intact eIF4GI protein is not required for the de novo synthesis of eIF4GI, suggesting its expression can continue under stress or infection conditions where eIF4GI is cleaved.

show abstract

“…This is made possible by the action of the poly-A binding protein, which binds simultaneously to the poly-A tail and the eIEF4G scaffold in the initiation complex. This interaction circularizes the mRNA molecule and allows the 3)-UTR to affect initiation efficacy [116,125]. Next, we will briefly discuss some of the known elements controlling translational efficacy.…”

Section: Translation Initiationmentioning

confidence: 99%

Effects of mRNA Untranslated Regions on Translational Efficiency of NMDA Receptor Subunits

VanDongen

2004

Neurosignals

View full text Add to dashboard Cite

Because NMDA receptors play critical roles in both neuronal survival and plasticity, their expression levels need to be carefully controlled. The number of functional NMDA receptors is temporally and spatially regulated at a hierarchy of levels, from gene transcription to protein trafficking. In this review we will focus on mechanisms for controlling functional expression of NMDA receptors that involve altering the efficacy of mRNA translation. One advantage of this level of control is that new receptors can be generated both rapidly and locally in response to appropriate synaptic activity patterns.

show abstract

The role of mRNA 5′‐noncoding and 3′‐end sequences on 40S ribosomal subunit recruitment, and how RNA viruses successfully compete with cellular mRNAs to ensure their own protein synthesis

Cited by 35 publications

References 82 publications

Replicase-Binding Sites on Plus- and Minus-Strand Brome Mosaic Virus RNAs and Their Roles in RNA Replication in Plant Cells

Replicase-Binding Sites on Plus- and Minus-Strand Brome Mosaic Virus RNAs and Their Roles in RNA Replication in Plant Cells

Translation of Eukaryotic Translation Initiation Factor 4GI (eIF4GI) Proceeds from Multiple mRNAs Containing a Novel Cap-dependent Internal Ribosome Entry Site (IRES) That Is Active during Poliovirus Infection

Effects of mRNA Untranslated Regions on Translational Efficiency of NMDA Receptor Subunits

Contact Info

Product

Resources

About