Related Experiment Video

Updated: Aug 8, 2026

Retroviral Scanning: Mapping MLV Integration Sites to Define Cell-specific Regulatory Regions
10:10

Retroviral Scanning: Mapping MLV Integration Sites to Define Cell-specific Regulatory Regions

Published on: May 28, 2017

Myb protein binds to human immunodeficiency virus 1 long terminal repeat (LTR) sequences and transactivates

P Dasgupta1, P Saikumar, C D Reddy

  • 1Wistar Institute of Anatomy and Biology, Philadelphia, PA 19104.

Proceedings of the National Academy of Sciences of the United States of America
|October 1, 1990
PubMed

Insights

The protooncogene c-myb binds to human immunodeficiency virus (HIV) long terminal repeats (LTRs), regulating viral transcription. This Myb protein binding to HIV-1 LTR sequences is sequence-specific and transactivates viral gene expression.

Area of Science:

  • Molecular Biology
  • Virology
  • Oncology

Background:

  • The protooncogene c-myb encodes a nuclear transcription factor involved in gene regulation.
  • c-myb expression is induced in lymphocytes and constitutively present in CD4+ T-cells and myeloid cells, which are targets for HIV.
  • Understanding factors regulating HIV transcription is crucial for therapeutic development.

Purpose of the Study:

  • To investigate the presence and function of Myb-binding motifs in human immunodeficiency virus (HIV) long terminal repeats (LTRs).
  • To determine if Myb protein can bind to and influence HIV-1 LTR-mediated transcription.

Main Methods:

  • Bioinformatic analysis to identify Myb-binding motifs in retroviral LTRs.
  • Electrophoretic mobility shift assays (EMSA) and DNase I protection assays using recombinant Myb protein and HIV-1 LTR sequences.
  • Reporter gene assays (chloramphenicol acetyltransferase) in HeLa cells to assess Myb's effect on HIV-1 LTR transcription.

Main Results:

  • HIV-1 LTR contains one high-affinity and multiple low-affinity Myb-binding sites.
  • Myb protein binds to HIV-1 LTR sequences in a sequence-specific manner.
  • Myb protein transactivates transcription mediated by the HIV-1 LTR.

Conclusions:

  • Myb protein can bind to specific sites within the HIV-1 LTR.
  • Myb protein acts as a transactivator of HIV-1 LTR transcription.
  • Myb protein binding to HIV LTR sequences is a potential regulatory mechanism for HIV-1 transcription.

More Related Videos

High Throughput In Vitro Assessment of Latency Reversing Agents on HIV Transcription and Splicing07:18

High Throughput In Vitro Assessment of Latency Reversing Agents on HIV Transcription and Splicing

Published on: January 22, 2019

Lentiviral Vector Platform for the Efficient Delivery of Epigenome-editing Tools into Human Induced Pluripotent Stem Cell-derived Disease Models13:47

Lentiviral Vector Platform for the Efficient Delivery of Epigenome-editing Tools into Human Induced Pluripotent Stem Cell-derived Disease Models

Published on: March 29, 2019

Related Concept Videos

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...
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...
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...
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...
Size and Structure of Viral Genomes01:26

Size and Structure of Viral Genomes

Viral genomes exhibit remarkable diversity in size, structure, and composition, influencing their replication strategies and interactions with host cells. These genomes consist of either DNA or RNA and may be linear or circular. Additionally, they can be single-stranded or double-stranded, with each configuration affecting how the virus propagates within a host. RNA viruses, for instance, generally have smaller genomes than DNA viruses, a factor that contributes to their high mutation rates and...
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...