scholarly journals Suppression of HPV-16 late L1 5′-splice site SD3632 by binding of hnRNP D proteins and hnRNP A2/B1 to upstream AUAGUA RNA motifs

2013 ◽  
Vol 41 (22) ◽  
pp. 10488-10508 ◽  
Author(s):  
Xiaoze Li ◽  
Cecilia Johansson ◽  
Jacob Glahder ◽  
Ann-Kristin Mossberg ◽  
Stefan Schwartz
Keyword(s):  
Splice Site ◽  
Rna Motifs ◽  
Hpv 16 ◽  
Hnrnp D

scholarly journals Multiple ASF/SF2 Sites in the Human Papillomavirus Type 16 (HPV-16) E4-Coding Region Promote Splicing to the Most Commonly Used 3′-Splice Site on the HPV-16 Genome

2010 ◽  
Vol 84 (16) ◽  
pp. 8219-8230 ◽  
Author(s):  
Monika Somberg ◽  
Stefan Schwartz
Keyword(s):  
Cervical Cancer ◽  
Human Papillomavirus ◽  
Splice Site ◽  
Binding Sites ◽  
Mrna Levels ◽  
Coding Region ◽  
Cervical Lesions ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
E6 And E7

ABSTRACT Our results presented here demonstrate that the most abundant human papillomavirus type 16 (HPV-16) mRNAs expressing the viral oncogenes E6 and E7 are regulated by cellular ASF/SF2, itself defined as a proto-oncogene and overexpressed in cervical cancer cells. We show that the most frequently used 3′-splice site on the HPV-16 genome, site SA3358, which is used to produce primarily E4, E6, and E7 mRNAs, is regulated by ASF/SF2. Splice site SA3358 is immediately followed by 15 potential binding sites for the splicing factor ASF/SF2. Recombinant ASF/SF2 binds to the cluster of ASF/SF2 sites. Mutational inactivation of all 15 sites abolished splicing to SA3358 and redirected splicing to the downstream-located, late 3′-splice site SA5639. Overexpression of a mutant ASF/SF2 protein that lacks the RS domain, also totally inhibited the usage of SA3358 and redirected splicing to the late 3′-splice site SA5639. The 15 ASF/SF2 binding sites could be replaced by an ASF/SF2-dependent, HIV-1-derived splicing enhancer named GAR. This enhancer was also inhibited by the mutant ASF/SF2 protein that lacks the RS domain. Finally, silencer RNA (siRNA)-mediated knockdown of ASF/SF2 caused a reduction in spliced HPV-16 mRNA levels. Taken together, our results demonstrate that the major HPV-16 3′-splice site SA3358 is dependent on ASF/SF2. SA3358 is used by the most abundantly expressed HPV-16 mRNAs, including those encoding E6 and E7. High levels of ASF/SF2 may therefore be a requirement for progression to cervical cancer. This is supported by our earlier findings that ASF/SF2 is overexpressed in high-grade cervical lesions and cervical cancer.

scholarly journals Polypyrimidine Tract Binding Protein Induces Human Papillomavirus Type 16 Late Gene Expression by Interfering with Splicing Inhibitory Elements at the Major Late 5′ Splice Site, SD3632

2008 ◽  
Vol 82 (7) ◽  
pp. 3665-3678 ◽  
Author(s):  
Monika Somberg ◽  
Xiaomin Zhao ◽  
Monika Fröhlich ◽  
Magnus Evander ◽  
Stefan Schwartz
Keyword(s):  
Gene Expression ◽  
Human Papillomavirus ◽  
Splice Site ◽  
Late Gene ◽  
Polypyrimidine Tract ◽  
Late Gene Expression ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
Polypyrimidine Tract Binding Protein ◽  
Cellular Factors

ABSTRACT We have initiated a screen for cellular factors that can induce human papillomavirus type 16 (HPV-16) late gene expression in human cancer cells. We report that the overexpression of polypyrimidine tract binding protein (PTB), also known as heterologous nuclear ribonucleoprotein I (hnRNP I), induces HPV-16 late gene expression in cells transfected with subgenomic HPV-16 plasmids or with full-length HPV-16 genomes and in persistently HPV-16-infected cells. In contrast, other hnRNPs such as hnRNP B1/A2, hnRNP F, and hnRNP Q do not induce HPV-16 late gene expression. PTB activates SD3632, the only 5′ splice site on the HPV-16 genome that is used exclusively by late mRNAs. PTB interferes with splicing inhibitory sequences located immediately upstream and downstream of SD3632, thereby activating late gene expression. One AU-rich PTB-responsive element was mapped to a 198-nucleotide sequence located downstream of SD3632. The deletion of this element induced HPV-16 late gene expression in the absence of PTB. Our results suggest that the overexpression of PTB interferes with cellular factors that interact with the inhibitory sequences. One may speculate that an increase in PTB levels or a reduction in the concentration of a PTB antagonist is required for the activation of HPV-16 late gene expression during the viral life cycle.

scholarly journals A Splicing Enhancer in the E4 Coding Region of Human Papillomavirus Type 16 Is Required for Early mRNA Splicing and Polyadenylation as Well as Inhibition of Premature Late Gene Expression

2005 ◽  
Vol 79 (18) ◽  
pp. 12002-12015 ◽  
Author(s):  
Margaret Rush ◽  
Xiaomin Zhao ◽  
Stefan Schwartz
Keyword(s):  
Gene Expression ◽  
Human Papillomavirus ◽  
Splice Site ◽  
Late Gene ◽  
Coding Region ◽  
Late Gene Expression ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
Early Region ◽  
Splicing Enhancer

ABSTRACT Successful inhibition of human papillomavirus type 16 (HPV-16) late gene expression early in the life cycle is essential for persistence of infection, the highest risk factor for cervical cancer. Our study aimed to locate regulatory RNA elements in the early region of HPV-16 that influence late gene expression. For this purpose, subgenomic HPV-16 expression plasmids under control of the strong human cytomegalovirus immediate early promoter were used. An exonic splicing enhancer that firmly supported the use of the E4 3′ splice site at position 3358 in the early region of the HPV-16 genome was identified. The enhancer was mapped to a 65-nucleotide AC-rich sequence located approximately 100 nucleotides downstream of the position 3358 3′ splice site. Deletion of the enhancer caused loss of both splicing at the upstream position 3358 3′ splice site and polyadenylation at the early polyadenylation signal, pAE. Direct splicing occurred at the competing L1 3′ splice site at position 5639 in the late region. Optimization of the position 3358 3′ splice site restored splicing to that site and polyadenylation at pAE. Additionally, a sequence of 40 nucleotides with a negative effect on late mRNA production was located immediately downstream of the enhancer. As the E4 3′ splice site is employed by both early and late mRNAs, the enhancer constitutes a key regulator of temporal HPV-16 gene expression, which is required for early mRNA production as well as for the inhibition of premature late gene expression.

scholarly journals Identification of an hnRNP A1-Dependent Splicing Silencer in the Human Papillomavirus Type 16 L1 Coding Region That Prevents Premature Expression of the Late L1 Gene

2004 ◽  
Vol 78 (20) ◽  
pp. 10888-10905 ◽  
Author(s):  
Xiaomin Zhao ◽  
Margaret Rush ◽  
Stefan Schwartz
Keyword(s):  
Human Papillomavirus ◽  
Splice Site ◽  
Early Stage ◽  
Eukaryotic Expression ◽  
Hnrnp A1 ◽  
Coding Region ◽  
Late Gene Expression ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
Splicing Silencer

ABSTRACT We have previously identified cis-acting RNA sequences in the human papillomavirus type 16 (HPV-16) L1 coding region which inhibit expression of L1 from eukaryotic expression plasmids. Here we have determined the function of one of these RNA elements, and we provide evidence that this RNA element is a splicing silencer which suppresses the use of the 3′ splice site located immediately upstream of the L1 AUG. We also show that this splice site is inefficiently utilized as a result of a suboptimal polypyrimidine tract. Introduction of point mutations in the L1 coding region that altered the RNA sequence without affecting the L1 protein sequence resulted in the inactivation of the splicing silencer and induced splicing to the L1 3′ splice site. These mutations also prevented the interaction of the RNA silencer with a 35-kDa cellular protein identified here as hnRNP A1. The splicing silencer in L1 inhibits splicing in vitro, and splicing can be restored by the addition of RNAs containing an hnRNP A1 binding site to the reaction, demonstrating that hnRNP A1 inhibits splicing of the late HPV-16 mRNAs through the splicing silencer sequence. While we show that one role of the splicing silencer is to determine the ratio between partially spliced L2/L1 mRNAs and spliced L1 mRNAs, we also demonstrate that it inhibits splicing from the major 5′ splice site in the early region to the L1 3′ splice site, thereby playing an essential role in preventing late gene expression at an early stage of the viral life cycle. We speculate that the activity of the splicing silencer and possibly the concentration of hnRNP A1 in the HPV-16-infected cell determines the ability of the virus to establish a persistent infection which remains undetected by the host immune surveillance.

scholarly journals Serine/arginine-rich protein 30c activates human papillomavirus type 16 L1 mRNA expression via a bimodal mechanism

2011 ◽  
Vol 92 (10) ◽  
pp. 2411-2421 ◽  
Author(s):  
Monika Somberg ◽  
Xiaoze Li ◽  
Cecilia Johansson ◽  
Beatrice Orru ◽  
Roger Chang ◽  
...  
Keyword(s):  
Human Papillomavirus ◽  
Mrna Expression ◽  
Capsid Protein ◽  
Splice Site ◽  
Inhibitory Effect ◽  
Mrna Splicing ◽  
Splice Sites ◽  
Hpv 16 ◽  
Human Papillomavirus Type 16 ◽  
Mitotic Cells

Two splice sites on the human papillomavirus type 16 (HPV-16) genome are used exclusively by the late capsid protein L1 mRNAs: SD3632 and SA5639. These splice sites are suppressed in mitotic cells. This study showed that serine/arginine-rich protein 30c (SRp30c), also named SFRS9, activated both SD3632 and SA5639 and induced production of L1 mRNA. Activation of HPV-16 L1 mRNA splicing by SRp30c required an intact arginine/serine-repeat (RS) domain of SRp30c. In addition to this effect, SRp30c could enhance L1 mRNA production indirectly by inhibiting the early 3′-splice site SA3358, which competed with the late 3′-splice site SA5639. SRp30c bound directly to sequences downstream of SA3358, suggesting that SRp30c inhibited the enhancer at SA3358 and caused a redirection of splicing to the late 3′-splice site SA5639. This inhibitory effect of SRp30c was independent of its RS domain. These results suggest that SRp30c can activate HPV-16 L1 mRNA expression via a bimodal mechanism: directly by stimulating splicing to late splice sites and indirectly by inhibiting competing early splice sites.

scholarly journals Eight Nucleotide Substitutions Inhibit Splicing to HPV-16 3′-Splice Site SA3358 and Reduce the Efficiency by which HPV-16 Increases the Life Span of Primary Human Keratinocytes

PLoS ONE ◽  
2013 ◽  
Vol 8 (9) ◽  
pp. e72776 ◽  
Author(s):  
Xiaoze Li ◽  
Cecilia Johansson ◽  
Carlos Cardoso Palacios ◽  
Anki Mossberg ◽  
Soniya Dhanjal ◽  
...  
Keyword(s):  
Life Span ◽  
Splice Site ◽  
Human Keratinocytes ◽  
Primary Human Keratinocytes ◽  
Nucleotide Substitutions ◽  
Hpv 16

hnRNP D

2006 ◽  
Author(s):  
Gary Brewer ◽  
Sandra Chesoni
Keyword(s):  
Hnrnp D

Emery-Dreifuss Muscular Dystrophy Type 1 in a 15-Year-Old Patient Due to a Novel Putative Splice-Site Mutation

2017 ◽  
Vol 48 (S 01) ◽  
pp. S1-S45
Author(s):  
O. Schwartz ◽  
J. Althaus ◽  
B. Fiedler ◽  
K. Heß ◽  
W. Paulus ◽  
...  
Keyword(s):  
Muscular Dystrophy ◽  
Splice Site ◽  
Splice Site Mutation ◽  
Site Mutation

Plattenepithelkarzinome im Kopf-Hals-Bereich: Therapiefortschritte und neue Erkenntnisse

2012 ◽  
Vol 03 (04) ◽  
pp. 195-195
Author(s):  
Angelika Bischoff
Keyword(s):  
Humane Papillomaviren ◽  
Hpv 16

Für mehr als zwei Jahrzehnte gab es keinen großen Fortschritt in der Erstlinienlinientherapie von rezidivierten und/oder metastasierten Plattenepithel-Karzinomen im Kopf-Hals-Bereich. Erst die Kombination des EGFR-Antikörpers Cetuximab (Erbitux®) mit einem Platin-5-FU-Regime brachte einen signifikanten überlebensvorteil. Als neuer pathogenetischer Faktor haben sich in letzter vor allem bei Oropharynxkarzinomen humane Papillomaviren (HPV 16) erwiesen.

Ectopic Transcript Analysis Indicates that Allelic Exclusion is an Important Cause of Type I Protein C Deficiency in Patients with Nonsense and Frameshift Mutations in the PROC Gene

1996 ◽  
Vol 75 (06) ◽  
pp. 870-876 ◽  
Author(s):  
José Manuel Soria ◽  
Lutz-Peter Berg ◽  
Jordi Fontcuberta ◽  
Vijay V Kakkar ◽  
Xavier Estivill ◽  
...  
Keyword(s):  
Splice Site ◽  
Protein C ◽  
Stop Codon ◽  
Premature Stop Codon ◽  
Allelic Exclusion ◽  
Polymorphism Analysis ◽  
Type I ◽  
Protein C Deficiency ◽  
Nonsense Mutations ◽  
Stop Codons

SummaryNonsense mutations, deletions and splice site mutations are a common cause of type I protein C deficiency. Either directly or indirectly by altering the reading frame, these' lesions generate or may generate premature stop codons and could therefore be expected to result in premature termination of translation. In this study, the possibility that such mutations could instead exert their pathological effects at an earlier stage in the expression pathway, through “allelic exclusion” at the RNA level, was investigated. Protein C (PROC) mRNA was analysed in seven Spanish type I protein C deficient patients heterozygous for two nonsense mutations, a 7bp deletion, a 2bp insertion and three splice site mutations. Ectopic RNA transcripts from patient and control lymphocytes were analysed by RT-PCR and direct sequencing of amplified PROC cDNA fragments. The nonsense mutations and the deletion were absent from the cDNAs indicating that only mRNA derived from the normal allele had been expressed. Similarly for the splice site mutations, only normal PROC cDNAs were obtained. In one case, exclusion of the mutated allele could be confirmed by polymorphism analysis. In contrast to these six mutations, the 2 bp insertion was not associated with loss of mRNA from the mutated allele. In this case, cDNA analysis revealed the absence of 19 bases from the PROC mRNA consistent with the generation and utilization of a cryptic splice site 3’ to the site of mutation, which would result in a frameshift and a premature stop codon. It is concluded that allelic exclusion is a common causative mechanism in those cases of type I protein C deficiency which result from mutations that introduce premature stop codons

Sign in / Sign up

Export Citation Format

Share Document