Related Experiment Video

Updated: Jun 2, 2026

Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
11:52

Analysis of LINE-1 Retrotransposition at the Single Nucleus Level

Published on: April 23, 2016

P bodies inhibit retrotransposition of endogenous intracisternal a particles

Chunye Lu1, Xavier Contreras, B Matija Peterlin

  • 1Department of Medicine, Microbiology, University of California at San Francisco, San Francisco, California 94143-0703, USA.

Journal of Virology
|April 29, 2011
PubMed

Insights

P bodies sequester messenger RNA (mRNA) away from Gag proteins, inhibiting the retrotransposition of intracisternal A-particle (IAP) elements in mammalian cells. Disrupting P bodies unexpectedly increased IAP retrotransposition and associated molecules.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Virology

Background:

  • mRNA-processing bodies (P bodies) are cellular structures involved in mRNA regulation.
  • P bodies are known to play roles in the retrotransposition of certain elements in yeast.
  • The function of P bodies in mammalian retrotransposition, specifically for intracisternal A-particles (IAPs), was previously unclear.

Purpose of the Study:

  • To investigate the role of P bodies in the retrotransposition of endogenous intracisternal A particles (IAPs) in mammalian cells.
  • To determine whether P bodies promote or inhibit IAP retrotransposition.
  • To elucidate the mechanism by which P bodies might influence IAP replication.

Main Methods:

  • Knockdown of key P body components (RCK and eIF4E-T) to disrupt P bodies.
  • Quantification of IAP retrotransposition, IAP transcripts, Gag proteins, and reverse transcription products.
  • Analysis of IAP mRNA localization (P bodies vs. polysomes) and Gag protein targeting (endoplasmic reticulum).

Main Results:

  • Disruption of P bodies significantly increased IAP retrotransposition, IAP transcripts, Gag proteins, and reverse transcription products.
  • The observed increase was not due to microRNA pathway impairment.
  • P body disruption caused a shift of IAP mRNA from nonpolysomal to polysomal fractions.
  • IAP mRNA localized to P bodies, while Gag proteins were targeted to the endoplasmic reticulum for IAP budding.

Conclusions:

  • P bodies act as a mechanism to inhibit IAP retrotransposition in mammalian cells.
  • By sequestering IAP mRNA, P bodies prevent its translation and subsequent IAP assembly.
  • The findings reveal a novel regulatory role for P bodies in the life cycle of endogenous retroelements.

More Related Videos

Recombinant Retroviral Production and Infection of B Cells09:19

Recombinant Retroviral Production and Infection of B Cells

Published on: February 18, 2011

Isolation of Cognate RNA-protein Complexes from Cells Using Oligonucleotide-directed Elution10:53

Isolation of Cognate RNA-protein Complexes from Cells Using Oligonucleotide-directed Elution

Published on: January 16, 2017

Related Concept Videos

LTR Retrotransposons03:08

LTR Retrotransposons

LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
Retroviruses02:33

Retroviruses

Retroviruses and retrotransposons both insert copies of their genetic elements into the genome of the host cell. Thus, the viral genes are passed on when the host genome is replicated or translated. A typical retroviral DNA sequence contains 3-4 genes that encode the different proteins required for its structural assembly and function as a molecular parasite. This DNA is transcribed into a single mRNA, which is very similar in structure to conventional mRNAs, i.e., it is capped at the 5’...
Non-LTR Retrotransposons03:18

Non-LTR Retrotransposons

As the name suggests, non-LTR retrotransposons lack the long terminal repeats characteristic of the LTR retrotransposons. Additionally, both LTR and non-LTR retrotransposons use distinct mechanisms of mobilization. Non-LTR retrotransposons are further divided into two classes - Long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs), both of which occur abundantly in most mammals, including humans. Some of the active non-LTR retrotransposons in humans are L1...
Retrovirus Life Cycles01:10

Retrovirus 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...
piRNA - Piwi-interacting RNAs02:57

piRNA - Piwi-interacting RNAs

PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
X-Inactivation01:58

X-Inactivation

The human X chromosome contains over ten times the number of genes as in the Y chromosome. Since males have only one X chromosome, and females have two, one might expect females to produce twice as many of the proteins, with undesirable results.