Intranuclear HSV-1 DNA ejection induces major mechanical transformations suggesting mechanoprotection of nucleus
Alex Evilevitch1, Sophia V Hohlbauch2
1Department of Experimental Medical Science, Lund University, Lund 22184, Sweden; Alex.Evilevitch@med.lu.se.
Summary
Herpes simplex virus type 1 (HSV-1) infection initially stiffens chromatin and softens the nuclear lamina. This mechanical adaptation protects nuclear integrity during viral DNA ejection and replication.
Area of Science:
- Cellular mechanics
- Virology
- Nuclear biology
Background:
- Nuclear integrity is crucial for cell survival under mechanical stress.
- Herpesviruses cause mechanical strain on the nuclear envelope during replication and assembly.
- The initial mechanical effects of herpesvirus infection on the nucleus were previously unknown.
Purpose of the Study:
- To investigate the mechanical changes in the nucleus immediately after herpes simplex virus type 1 (HSV-1) DNA ejection.
- To understand how nuclear integrity is maintained during the early stages of HSV-1 infection.
Main Methods:
- Utilized an atomic force microscopy force volume mapping approach.
- Studied cell-free reconstituted nuclei with docked HSV-1 capsids.
- Analyzed the mechanical response of the nuclear lamina and chromatin to intranuclear DNA ejection.
Main Results:
- Chromatin stiffness (Young's modulus) increased approximately 14-fold.
- The nuclear lamina exhibited softening (increased elasticity).
- These changes occurred immediately following intranuclear HSV-1 DNA ejection.
Conclusions:
- Chromatin stiffening and lamina softening represent a mechanoprotective mechanism.
- Stiffened chromatin maintains nuclear morphology.
- Lamina softening acts as a shock absorber, preventing nuclear membrane rupture and facilitating viral genome replication.
More Related Videos
08:26Purification of Viral DNA for the Identification of Associated Viral and Cellular Proteins
Published on: August 31, 2017
13.8K
13:22Detection of the Genome and Transcripts of a Persistent DNA Virus in Neuronal Tissues by Fluorescent In situ Hybridization Combined with Immunostaining
Published on: January 23, 2014
18.4K
Related Concept Videos
01:45Regulation of Nuclear Protein Sorting
2.5K
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
2.5K
02:54Nucleosome Remodeling
9.8K
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
9.8K
01:10Intracellular Movement of Viruses and Bacteria
3.0K
Intracellular bacteria and viruses often comprise a group of highly infectious pathogens that can cause several diseases. Bacterial pathogens include those belonging to the genus Rickettsia responsible for conditions such as rocky mountain spotted fever and the Mediterranean spotted fever; Chlamydia, a genus responsible for a sexually transmitted disease; Coxiella burnetii, an agent responsible for Q fever. Viral pathogens include vaccinia—a poxvirus, and herpes simplex virus—a...
3.0K
02:31Homologous Recombination
54.7K
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
54.7K
01:08Nucleotide Excision Repair
37.7K
Overview
37.7K
00:55DNA Helicases
22.5K
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
22.5K