Reprogramming of the HepG2 genome by long interspersed nuclear element-1

Pasano Bojang, Ruth A. Roberts, Mark J. Anderton, Kenneth Ramos

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Long Interspersed Nuclear Element- 1 (LINE-1 or L1) is an autonomous, mobile element within the human genome that transposes via a "copy and paste" mechanism and relies upon L1-encoded endonuclease and reverse transcriptase (RT) activities to compromise genome integrity. L1 has been implicated in various forms of cancer, but its role in the regulation of the oncogenic phenotype is not understood. The present studies were conducted to evaluate mechanisms of genetic regulatory control in HepG2 cells by human L1, or a D702Y mutant deficient in RT activity, and their influence on cellular phenotype. Forced expression of synthetic L1 ORF1p and ORF2p was associated with formation of cytoplasmic foci and minor association with the nuclear compartment. While de novo L1 mobilizations were only identified in cells expressing wild type L1, and were absent in the D702Y mutant, changes in gene expression profiles involved RT dependent as well as RT independent mechanisms. Synthetic L1 altered the expression of 24 in silico predicted genetic targets; ten of which showed RT-dependence, ten RT-independence, and four reciprocal regulatory control by both wild type and RT mutant. Of five targets examined, only VCAM1 and PTPRB colocalized with newly retrotransposed wild type L1. Biological discretization to partition patterns of gene expression into unique frequencies identified adhesion, inflammation, and cellular metabolism as key processes targeted for molecular interference with disruption of epithelial-to-mesenchymal programming seen irrespective of the RT phenotype. These findings establish L1 as a key regulator of genome plasticity and EMT via mechanisms independent of RT activity.

Original languageEnglish (US)
Pages (from-to)812-825
Number of pages14
JournalMolecular Oncology
Volume7
Issue number4
DOIs
StatePublished - Aug 2013
Externally publishedYes

Fingerprint

RNA-Directed DNA Polymerase
Genome
Phenotype
Long Interspersed Nucleotide Elements
Endonucleases
Hep G2 Cells
Human Genome
Ointments
Transcriptome
Computer Simulation
Inflammation
Gene Expression

Keywords

  • Epithelial-to-mesenchymal transition
  • Genetic reprogramming
  • Long interspersed nuclear element-1
  • Retrotransposons
  • Reverse transcriptase

ASJC Scopus subject areas

  • Cancer Research
  • Genetics
  • Molecular Medicine

Cite this

Reprogramming of the HepG2 genome by long interspersed nuclear element-1. / Bojang, Pasano; Roberts, Ruth A.; Anderton, Mark J.; Ramos, Kenneth.

In: Molecular Oncology, Vol. 7, No. 4, 08.2013, p. 812-825.

Research output: Contribution to journalArticle

Bojang, Pasano ; Roberts, Ruth A. ; Anderton, Mark J. ; Ramos, Kenneth. / Reprogramming of the HepG2 genome by long interspersed nuclear element-1. In: Molecular Oncology. 2013 ; Vol. 7, No. 4. pp. 812-825.
@article{f9e70544ae9e4b87a7578b21d50fae67,
title = "Reprogramming of the HepG2 genome by long interspersed nuclear element-1",
abstract = "Long Interspersed Nuclear Element- 1 (LINE-1 or L1) is an autonomous, mobile element within the human genome that transposes via a {"}copy and paste{"} mechanism and relies upon L1-encoded endonuclease and reverse transcriptase (RT) activities to compromise genome integrity. L1 has been implicated in various forms of cancer, but its role in the regulation of the oncogenic phenotype is not understood. The present studies were conducted to evaluate mechanisms of genetic regulatory control in HepG2 cells by human L1, or a D702Y mutant deficient in RT activity, and their influence on cellular phenotype. Forced expression of synthetic L1 ORF1p and ORF2p was associated with formation of cytoplasmic foci and minor association with the nuclear compartment. While de novo L1 mobilizations were only identified in cells expressing wild type L1, and were absent in the D702Y mutant, changes in gene expression profiles involved RT dependent as well as RT independent mechanisms. Synthetic L1 altered the expression of 24 in silico predicted genetic targets; ten of which showed RT-dependence, ten RT-independence, and four reciprocal regulatory control by both wild type and RT mutant. Of five targets examined, only VCAM1 and PTPRB colocalized with newly retrotransposed wild type L1. Biological discretization to partition patterns of gene expression into unique frequencies identified adhesion, inflammation, and cellular metabolism as key processes targeted for molecular interference with disruption of epithelial-to-mesenchymal programming seen irrespective of the RT phenotype. These findings establish L1 as a key regulator of genome plasticity and EMT via mechanisms independent of RT activity.",
keywords = "Epithelial-to-mesenchymal transition, Genetic reprogramming, Long interspersed nuclear element-1, Retrotransposons, Reverse transcriptase",
author = "Pasano Bojang and Roberts, {Ruth A.} and Anderton, {Mark J.} and Kenneth Ramos",
year = "2013",
month = "8",
doi = "10.1016/j.molonc.2013.04.003",
language = "English (US)",
volume = "7",
pages = "812--825",
journal = "Molecular Oncology",
issn = "1574-7891",
publisher = "Elsevier",
number = "4",

}

TY - JOUR

T1 - Reprogramming of the HepG2 genome by long interspersed nuclear element-1

AU - Bojang, Pasano

AU - Roberts, Ruth A.

AU - Anderton, Mark J.

AU - Ramos, Kenneth

PY - 2013/8

Y1 - 2013/8

N2 - Long Interspersed Nuclear Element- 1 (LINE-1 or L1) is an autonomous, mobile element within the human genome that transposes via a "copy and paste" mechanism and relies upon L1-encoded endonuclease and reverse transcriptase (RT) activities to compromise genome integrity. L1 has been implicated in various forms of cancer, but its role in the regulation of the oncogenic phenotype is not understood. The present studies were conducted to evaluate mechanisms of genetic regulatory control in HepG2 cells by human L1, or a D702Y mutant deficient in RT activity, and their influence on cellular phenotype. Forced expression of synthetic L1 ORF1p and ORF2p was associated with formation of cytoplasmic foci and minor association with the nuclear compartment. While de novo L1 mobilizations were only identified in cells expressing wild type L1, and were absent in the D702Y mutant, changes in gene expression profiles involved RT dependent as well as RT independent mechanisms. Synthetic L1 altered the expression of 24 in silico predicted genetic targets; ten of which showed RT-dependence, ten RT-independence, and four reciprocal regulatory control by both wild type and RT mutant. Of five targets examined, only VCAM1 and PTPRB colocalized with newly retrotransposed wild type L1. Biological discretization to partition patterns of gene expression into unique frequencies identified adhesion, inflammation, and cellular metabolism as key processes targeted for molecular interference with disruption of epithelial-to-mesenchymal programming seen irrespective of the RT phenotype. These findings establish L1 as a key regulator of genome plasticity and EMT via mechanisms independent of RT activity.

AB - Long Interspersed Nuclear Element- 1 (LINE-1 or L1) is an autonomous, mobile element within the human genome that transposes via a "copy and paste" mechanism and relies upon L1-encoded endonuclease and reverse transcriptase (RT) activities to compromise genome integrity. L1 has been implicated in various forms of cancer, but its role in the regulation of the oncogenic phenotype is not understood. The present studies were conducted to evaluate mechanisms of genetic regulatory control in HepG2 cells by human L1, or a D702Y mutant deficient in RT activity, and their influence on cellular phenotype. Forced expression of synthetic L1 ORF1p and ORF2p was associated with formation of cytoplasmic foci and minor association with the nuclear compartment. While de novo L1 mobilizations were only identified in cells expressing wild type L1, and were absent in the D702Y mutant, changes in gene expression profiles involved RT dependent as well as RT independent mechanisms. Synthetic L1 altered the expression of 24 in silico predicted genetic targets; ten of which showed RT-dependence, ten RT-independence, and four reciprocal regulatory control by both wild type and RT mutant. Of five targets examined, only VCAM1 and PTPRB colocalized with newly retrotransposed wild type L1. Biological discretization to partition patterns of gene expression into unique frequencies identified adhesion, inflammation, and cellular metabolism as key processes targeted for molecular interference with disruption of epithelial-to-mesenchymal programming seen irrespective of the RT phenotype. These findings establish L1 as a key regulator of genome plasticity and EMT via mechanisms independent of RT activity.

KW - Epithelial-to-mesenchymal transition

KW - Genetic reprogramming

KW - Long interspersed nuclear element-1

KW - Retrotransposons

KW - Reverse transcriptase

UR - http://www.scopus.com/inward/record.url?scp=84880748103&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84880748103&partnerID=8YFLogxK

U2 - 10.1016/j.molonc.2013.04.003

DO - 10.1016/j.molonc.2013.04.003

M3 - Article

C2 - 23648019

AN - SCOPUS:84880748103

VL - 7

SP - 812

EP - 825

JO - Molecular Oncology

JF - Molecular Oncology

SN - 1574-7891

IS - 4

ER -