Related Experiment Video

Updated: Sep 23, 2026

Temporal Analysis of the Nuclear-to-cytoplasmic Translocation of a Herpes Simplex Virus 1 Protein by Immunofluorescent Confocal Microscopy
06:40

Temporal Analysis of the Nuclear-to-cytoplasmic Translocation of a Herpes Simplex Virus 1 Protein by Immunofluorescent Confocal Microscopy

Published on: November 4, 2018

Microtubule network facilitates nuclear targeting of human cytomegalovirus capsid

K Ogawa-Goto1, K Tanaka, W Gibson

  • 1Department of Pathology, National Institute of Infectious Diseases, Shinjuku, Tokyo 162-8640, Japan. tsata@nih.go.jp

Journal of Virology
|July 15, 2003
PubMed

Insights

Incoming human cytomegalovirus (HCMV) capsids require host cell microtubules for nuclear transport. This association is essential for efficient immediate-early gene expression after HCMV infection.

Area of Science:

  • Virology
  • Cell Biology
  • Molecular Biology

Background:

  • Human cytomegalovirus (HCMV) is a significant pathogen.
  • Understanding viral entry and intracellular transport is crucial for developing antiviral strategies.

Purpose of the Study:

  • To investigate the role of the host cytoskeleton, specifically microtubules, in the intracellular transport of HCMV capsids.
  • To determine the necessity of microtubule-dependent transport for early HCMV gene expression.

Main Methods:

  • Western blot analysis to quantify IE1 antigen levels after drug treatments.
  • Immunofluorescent assay (IFA) to monitor viral capsid (pUL83) localization.
  • Ultrastructural analysis to visualize capsid-microtubule interactions.
  • Drug treatments (nocodazole, colchicine, cytochalasin B) to disrupt cytoskeletal components.

Main Results:

  • Microtubule depolymerization significantly reduced IE1 antigen levels, while disruption of actin filaments had no effect.
  • HCMV entry into cells occurred normally even without an intact microtubule network.
  • HCMV capsids were found to associate closely with microtubules.
  • In the absence of microtubules, capsids failed to reach the nuclear vicinity.

Conclusions:

  • HCMV capsids utilize the host microtubule network for efficient transport to the nucleus.
  • This microtubule-mediated transport is a prerequisite for initiating immediate-early gene expression in HCMV infection.

More Related Videos

Nucleocapsid Annealing-Mediated Electrophoresis (NAME) Assay Allows the Rapid Identification of HIV-1 Nucleocapsid Inhibitors08:33

Nucleocapsid Annealing-Mediated Electrophoresis (NAME) Assay Allows the Rapid Identification of HIV-1 Nucleocapsid Inhibitors

Published on: January 19, 2015

Visualization of HIV-1 Gag Binding to Giant Unilamellar Vesicle (GUV) Membranes08:21

Visualization of HIV-1 Gag Binding to Giant Unilamellar Vesicle (GUV) Membranes

Published on: July 28, 2016

Related Concept Videos

Cytomegalovirus Disease01:27

Cytomegalovirus Disease

Cytomegalovirus (CMV) disease is caused by human cytomegalovirus, a double-stranded DNA virus of the Herpesviridae family. While primary CMV infection is often asymptomatic in immunocompetent individuals, the virus can cause severe disease in neonates and immunocompromised patients. CMV is the most common cause of congenital viral infection in the United States, and a major pathogen in solid organ and hematopoietic stem cell transplant recipients.CMV is transmitted via bodily fluids, sexual...
Microtubule Formation01:23

Microtubule Formation

Microtubules are dynamic structures that undergo continuous assembly and disassembly. They originate from specialized multi-protein complexes known as microtubule organizing centers or MTOCs. Within the MTOC, the point of origin of the microtubule is known as the minus end, while the end radiating outward is the plus end. Microtubules serve two primary functions — the organization of spindle complexes to separate sister chromatids during mitotic or meiotic cell division and the formation of...
Vesicular Tubular Clusters01:45

Vesicular Tubular Clusters

After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
Intralumenal Vesicles and Multivesicular Bodies01:38

Intralumenal Vesicles and Multivesicular Bodies

Intraluminal vesicles (ILVs) are small vesicles 50-80 nm in diameter formed during the maturation of early endosomes. A specialized endosome containing numerous ILVs is called a multivesicular body (MVB). ILVs contain internalized molecules such as antigens, nucleic acids, proteins, and metabolites. Some of these molecules are released from the MVBs inside exosomes and are transported to other cells. Other MVBs contain molecules that are retained in the ILVs and are later degraded within the...
Assembly of Complex Microtubule Structures01:32

Assembly of Complex Microtubule Structures

Complex microtubule structures are present in resting cells and in dividing cells. In resting cells, they are responsible for maintaining the cellular architecture, tracks for intracellular transport, positioning of organelles, assembly of cilia and flagella. They mediate the bipolar spindle assembly for chromosomal segregation and positioning of the cell division plate in dividing cells. The formation of microtubule complex structures depends on the cell type, cell stage, and cell function.
Inhibitors of Virion Maturation and Assembly01:19

Inhibitors of Virion Maturation and Assembly

As part of their replication cycle, certain viruses synthesize long precursor proteins called polyproteins within infected host cells. In human immunodeficiency virus (HIV), two major polyproteins are produced: Gag and Gag-Pol. The Gag polyprotein supplies the structural components of the virus, while Gag-Pol includes essential viral enzymes such as reverse transcriptase, integrase, and protease. After synthesis, these polyproteins move to the host cell membrane, where they assemble into an...