Related Experiment Video

Updated: Dec 23, 2025

Measurement of BK-polyomavirus Non-Coding Control Region Driven Transcriptional Activity Via Flow Cytometry
11:54

Measurement of BK-polyomavirus Non-Coding Control Region Driven Transcriptional Activity Via Flow Cytometry

Published on: July 13, 2019

9.3K

High expression of JC polyomavirus-encoded microRNAs in progressive multifocal leukoencephalopathy tissues and its

Kenta Takahashi1, Yuko Sato1, Tsuyoshi Sekizuka2

  • 1Department of Pathology, National Institute of Infectious Diseases, Shinjuku, Tokyo, Japan.

Plos Pathogens
|April 24, 2020
PubMed

Insights

JC polyomavirus (JCPyV) microRNA (miR-J1) is highly expressed in the nuclei of infected cells in progressive multifocal leukoencephalopathy (PML) tissue. This viral miRNA may repress JCPyV replication, suggesting its diagnostic potential for PML.

Area of Science:

  • Virology
  • Molecular Biology
  • Pathology

Background:

  • JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy (PML) in immunocompromised individuals.
  • JCPyV encodes a microRNA (miRNA), miR-J1, within its genome.
  • Localization of viral miRNAs in pathological tissues has not been previously reported.

Purpose of the Study:

  • To investigate the localization and potential role of JCPyV-encoded miRNA (miR-J1) in PML.
  • To explore the diagnostic utility of in situ hybridization for viral miRNAs in PML.

Main Methods:

  • In situ hybridization was used to detect miR-J1 expression in PML tissue samples.
  • Immunohistochemistry confirmed JCPyV presence.
  • Real-time reverse transcription PCR and next-generation sequencing quantified miR-J1 levels.
  • Recombinant JCPyV with deleted/mutated miR-J1 was used to assess its role in viral protein production.

Main Results:

  • High miR-J1 expression was detected in the nuclei of JCPyV-infected cells in PML tissues.
  • miR-J1 was also detected in BK polyomavirus-associated nephropathy lesions.
  • miR-J1 was significantly more abundant in PML tissues than non-PML tissues.
  • Deletion of miR-J1 in recombinant JCPyV increased viral protein production, suggesting a repressive role.

Conclusions:

  • Viral miRNAs, such as miR-J1, are localized within infected cells in virus-associated diseases.
  • miR-J1 may play a regulatory role in JCPyV replication.
  • In situ hybridization for viral miRNAs could be a valuable diagnostic tool for PML.

More Related Videos

Merkel Cell Polyomavirus Infection and Detection13:45

Merkel Cell Polyomavirus Infection and Detection

Published on: February 7, 2019

10.3K
MicroRNA-based Regulation of Picornavirus Tropism09:05

MicroRNA-based Regulation of Picornavirus Tropism

Published on: February 6, 2017

7.9K

Related Concept Videos

MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...
3.6K
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After...
23.7K
Mechanisms of Retrovirus-induced Cancers01:51

Mechanisms of Retrovirus-induced Cancers

Retroviruses are RNA viruses that have been shown to cause cancers in diverse species, including chickens, mice, cats, and monkeys. The RNA genomes of these viruses are first reverse-transcribed into single and then double-stranded DNA (dsDNA) copies. This dsDNA called proviral DNA then integrates into the host genome. Subsequently, the host cell transcribes the proviral DNA in concert with the chromosomal DNA. This leads to the production of viral RNA and proteins that assemble at the host...
6.7K
Regulation of Expression at Multiple Steps01:23

Regulation of Expression at Multiple Steps

The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the...
1.3K
EPS and iPS Cells in Disease Research01:21

EPS and iPS Cells in Disease Research

Embryonic and induced pluripotent stem cells are excellent models for disease research because of their ability to self-renew and differentiate into most cell types. Somatic cells from a patient are isolated and reprogrammed into induced pluripotent stem cells or iPSCs. These iPSCs are later differentiated into the desired cell type, which mirrors the diseased cell of the patient. In this way, disease models have been created for investigating diseases such as Down syndrome, type I diabetes,...
3.2K
Immune Response Against Viral Pathogens01:29

Immune Response Against Viral Pathogens

The immune system's response to viral infections is a complex and coordinated process involving natural killer (NK) cells, T cell-mediated responses, and antibody-mediated responses.
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
1.6K