Related Experiment Video
Updated: May 29, 2026
10:53
Isolation of Cognate RNA-protein Complexes from Cells Using Oligonucleotide-directed Elution
Published on: January 16, 2017
A physical link between the pseudorabies virus capsid and the nuclear egress complex
Mindy Leelawong1, Dongsheng Guo, Gregory A Smith
1Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, 303 E. Chicago Ave., Morton 3-603, Chicago, IL 60611, USA.
Journal of Virology
|September 2, 2011
Summary
The herpesvirus nuclear egress complex protein pUL31 binds to capsids only when pUL34 is absent. This conditional binding is crucial for targeting DNA-containing capsids during nuclear egress.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Herpesvirus capsids exit the nucleus via the inner nuclear membrane.
- This nuclear egress requires two conserved viral proteins: pUL31 and pUL34.
Purpose of the Study:
- To investigate the capsid-binding properties of the pUL31 protein.
- To determine the role of pUL34 in mediating the pUL31-capsid interaction.
Main Methods:
- Fluorescence microscopy to visualize protein-capsid interactions.
- Western blot analysis of purified intranuclear capsids.
- Testing interactions with viral proteins pUL25, pUL6, and pUL33.
Main Results:
- pUL31 is a conditional capsid-binding protein, unmasked in the absence of pUL34.
- The pUL31-capsid interaction was confirmed using microscopy and Western blot.
- None of the tested viral proteins (pUL25, pUL6, pUL33) were required for pUL31-capsid binding.
Conclusions:
- Provides the first evidence of a herpesvirus nuclear egress complex interacting with capsids.
- Suggests a mechanism for selective targeting of DNA-containing capsids for nuclear egress.
Related Concept Videos
02:31Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
02:31Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
01:10Retrovirus Life Cycles
Retroviruses have a single-stranded RNA genome that undergoes a special form of replication. Once the retrovirus has entered the host cell, an enzyme called reverse transcriptase synthesizes double-stranded DNA from the retroviral RNA genome. This DNA copy of the genome is then integrated into the host’s genome inside the nucleus via an enzyme called integrase. Consequently, the retroviral genome is transcribed into RNA whenever the host’s genome is transcribed, allowing the retrovirus to...
01:28Rabies
Rabies is a lethal zoonotic disease caused by a single-stranded, negative-sense RNA virus of the Lyssavirus genus, within the family Rhabdoviridae. Its primary mode of transmission to humans is through bites or saliva-contaminated scratches from infected mammals such as dogs, bats, raccoons, or foxes. Transmission can also occur if infectious saliva contacts abraded skin or intact mucous membranes, including the conjunctiva.Viral Entry and Early ReplicationOnce introduced at the bite or scratch...
00:56Viral Structure
Viruses are extraordinarily diverse in shape and size, but they all have several structural features in common. All viruses have a core that contains a DNA- or RNA-based genome. The core is surrounded by a protective coat of proteins called the capsid. The capsid is composed of subunits called capsomeres. The capsid and genome-containing core are together known as the nucleocapsid.
01:42Nuclear Export
The nucleus restricts several proteins within and allows others to pass. The restricted proteins possess a nuclear retention sequence or NRS, anchoring them to the nuclear lamins and preventing their transport to the cytosol. The non-restricted proteins, after their synthesis, are transported to their site of action, such as the cytosol or other organelles, with the help of nuclear export signals or NES.
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
NES are of three types- the canonical 10-residue long leucine-rich signal and other...