Dataset Information

The herpes viral transcription factor ICP4 forms a novel DNA recognition complex.

ABSTRACT: The transcription factor ICP4 from herpes simplex virus has a central role in regulating the gene expression cascade which controls viral infection. Here we present the crystal structure of the functionally essential ICP4 DNA binding domain in complex with a segment from its own promoter, revealing a novel homo-dimeric fold. We also studied the complex in solution by small angle X-Ray scattering, nuclear magnetic resonance and surface-plasmon resonance which indicated that, in addition to the globular domain, a flanking intrinsically disordered region also recognizes DNA. Together the data provides a rationale for the bi-partite nature of the ICP4 DNA recognition consensus sequence as the globular and disordered regions bind synergistically to adjacent DNA motifs. Therefore in common with its eukaryotic host, the viral transcription factor ICP4 utilizes disordered regions to enhance the affinity and tune the specificity of DNA interactions in tandem with a globular domain.

SUBMITTER: Tunnicliffe RB

PROVIDER: S-EPMC5737704 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The herpes viral transcription factor ICP4 forms a novel DNA recognition complex.

Tunnicliffe Richard B RB Lockhart-Cairns Michael P MP Levy Colin C Mould A Paul AP Jowitt Thomas A TA Sito Hilary H Baldock Clair C Sandri-Goldin Rozanne M RM Golovanov Alexander P AP

Nucleic acids research 20170701 13

The transcription factor ICP4 from herpes simplex virus has a central role in regulating the gene expression cascade which controls viral infection. Here we present the crystal structure of the functionally essential ICP4 DNA binding domain in complex with a segment from its own promoter, revealing a novel homo-dimeric fold. We also studied the complex in solution by small angle X-Ray scattering, nuclear magnetic resonance and surface-plasmon resonance which indicated that, in addition to the gl ...[more]

PMID: 28505309

Similar Datasets

Project description:Herpes simplex virus 1 (HSV-1) transcription is tightly regulated in a temporal cascade, utilizing cellular RNA polymerase. We previously observed that infection with HSV-1 mutants lacking immediate early (IE) genes α0, α4, and α22 exhibited high levels of aberrant transcription across the viral genome at just 1.5 hpi. The strongest effect occurred in the absence of full-length ICP4 which is both an essential transcriptional activator and repressor. The goal of the current study was to define the mechanism of ICP4-mediated early transcriptional repression on the viral genome. Using PRO-Cap, PRO-Seq, GRO-Seq, and Nanopore direct RNA sequencing to analyze viral transcription, we found that initiation was elevated at viral promoters of all temporal classes in the absence of ICP4. Despite higher levels of initiation, transcription of non-IE genes was stalled within gene bodies and did not lead to production of mature mRNA. Thus, ICP4-independent mechanisms limit expression of viral genes that initiate prematurely. GRO-seq data also indicated rapid release from promoter proximal pausing, and rapid progression along HSV IE gene bodies, with termination as an important rate-limiting regulatory step. These findings highlight multiple mechanisms that HSV-1 employs to regulate early transcription and shows that ICP4's repressive role is to restrict initiation, thereby ensuring correct progression of the temporal cascade. IMPORTANCE Infection with herpes simplex virus 1 (HSV-1) leads to lifelong infection due to the virus's remarkable ability to control transcription of its own genome, resulting in two transcriptional programs: lytic (highly active) and latent (restricted). The lytic program requires immediate early (IE) proteins to first repress transcription of late viral genes, which then undergo sequential de-repression, leading to a specific sequence of gene expression. Here, we show that the IE ICP4 functions to regulate the cascade by limiting RNA polymerase initiation at immediate early times. However, late viral genes that initiate too early in the absence of ICP4 do not yield mRNA as transcription stalls within gene bodies. It follows that other regulatory steps intercede to prevent elongation of genes at the incorrect time, demonstrating the precise control HSV-1 exerts over its own transcription.

Dataset Information

The herpes viral transcription factor ICP4 forms a novel DNA recognition complex.

Publications

The herpes viral transcription factor ICP4 forms a novel DNA recognition complex.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets