Related Experiment Video

Updated: Jul 15, 2026

ABCG5/G8 Crystallization in a Lipidic Bicelle Environment for X-Ray Crystallography
06:47

ABCG5/G8 Crystallization in a Lipidic Bicelle Environment for X-Ray Crystallography

Published on: August 25, 2023

Expression of ATP binding cassette-transporter ABCG1 prevents cell death by transporting cytotoxic

Thomas Engel1, Frank Kannenberg, Manfred Fobker

  • 1Leibniz-Institute for Arteriosclerosis Research, Westphalian Wilhelms-University, 48149 Muenster, Germany. engeltho@uni-muenster.de <engeltho@uni-muenster.de>

FEBS Letters
|April 6, 2007
PubMed

Insights

ATP-binding cassette transporter G1 (ABCG1) facilitates the detoxification of 7beta-hydroxycholesterol (7beta-HC). This suggests ABCG1 plays a crucial role in preventing cell death and may aid in preventing neurodegenerative and cardiovascular diseases.

Area of Science:

  • Cellular biology
  • Biochemistry
  • Molecular mechanisms of disease

Background:

  • Oxysterols, derived from cholesterol, can induce cell death through necrosis or apoptosis.
  • Detoxification of oxysterols primarily occurs in the liver, necessitating transport from peripheral tissues.
  • ATP-binding cassette (ABC) transporters are known to export cytotoxic compounds.

Purpose of the Study:

  • To investigate the potential role of ATP-binding cassette transporter G1 (ABCG1) in oxysterol transport.
  • To determine if ABCG1 is involved in the cellular detoxification of oxysterols.
  • To explore the functional consequences of ABCG1 activation by oxysterols.

Main Methods:

  • Stable expression of ABCG1 in TetOff HeLa cells.
  • Measurement of intracellular oxysterol uptake, specifically 7beta-hydroxycholesterol (7beta-HC).
  • Assessment of mitochondrial membrane potential and reactive oxygen species production in response to 7beta-HC.

Main Results:

  • ABCG1 expression led to decreased uptake of 7beta-hydroxycholesterol (7beta-HC) in HeLa cells.
  • Other physiologically relevant oxysterols were not affected in their uptake.
  • 7beta-HC exposure in ABCG1-expressing cells triggered mitochondrial hyperpolarization and reactive oxygen species generation, indicating transporter activation and energy consumption.

Conclusions:

  • ABCG1 functions in the detoxification of 7beta-hydroxycholesterol (7beta-HC).
  • ABCG1 activation by 7beta-HC suggests a protective role against oxysterol-induced cell death.
  • This protective mechanism may be significant in preventing neurodegenerative and cardiovascular diseases.

More Related Videos

Cholesterol Efflux Assay07:54

Cholesterol Efflux Assay

Published on: March 6, 2012

Related Concept Videos

ABC Transporters: Exporter01:31

ABC Transporters: Exporter

ATP-binding cassette or ABC transporter is the largest superfamily of integral membrane proteins. The transporters have transmembrane-binding domains (TMDs) and nucleotide-binding domains (NBDs). The TMDs are specific to their substrates, whereas the NBDs are similar to engines that complete ATP hydrolysis to complete the substrate transport. They can be full transporters consisting of two TMDs and NBDs, half transporters with one TMD and NBD, while some encoded with a single TMD or NBD are...
Pharmacogenetics of Drug Transporters: P-Glycoprotein and Solute Carrier Transporters01:16

Pharmacogenetics of Drug Transporters: P-Glycoprotein and Solute Carrier Transporters

The pharmacogenetics of drug transporters is increasingly recognized as a critical factor influencing interindividual variability in drug absorption, distribution, and elimination. These membrane-bound proteins regulate drugs' movement across cellular barriers by actively pumping them out (efflux) or facilitating their uptake (influx). Among the major transporter families, ATP-binding cassette (ABC) and solute carrier (SLC) transporters play particularly prominent roles. Genetic polymorphisms...
Carrier-Mediated Transport01:06

Carrier-Mediated Transport

Carrier-mediated transport is a pivotal process in drug absorption, particularly for lipid-insoluble drugs, and encompasses facilitated diffusion and active transport. Facilitated diffusion allows drugs to move along their concentration gradient without energy expenditure, while active transport utilizes ATP to drive drug movement against this gradient.
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
ABC Transporters: Importer01:27

ABC Transporters: Importer

ATP-binding cassette or ABC transporters are a class of ATP-driven pumps that hydrolyze ATP to move solutes across the membrane. They can be grouped into importers and exporters. While exporters are present in all domains of life, importers exist only in bacteria and some plants.
In bacteria, based on the number of transmembrane helices and the chemical nature of their substrates, the ABC importers can be divided into three types: