Related Experiment Video
Updated: Jun 21, 2026

Isolation and Differentiation of Stromal Vascular Cells to Beige/Brite Cells
Published on: March 28, 2013
Expression and stability of two isoforms of ABCG1 in human vascular cells
Ingrid C Gelissen1, Sian Cartland, Andrew J Brown
1Centre for Vascular Research, University of New South Wales, Sydney, Australia.
Objective:
To evaluate the expression of two ABCG1 isoforms that differ in the presence or absence of a 12 amino acid (AA) peptide between the ABC cassette and the transmembrane region, termed ABCG1(+12) and ABCG1(-12), respectively, in human vascular cells and tissues.
Methods And Results:
mRNA for both isoforms was expressed in human macrophages, vascular endothelial and smooth muscle cells as well as whole human spleen, lung, liver and brain tissue. However, ABCG1(+12) was not expressed in mouse tissues. 2D gel electrophoresis of ABCG1 protein indicated that both protein isoforms were expressed in human macrophages. Furthermore the half-lives of the two ABCG1 protein isoforms, stably expressed in CHOK1 cells, measured under basal conditions were different, suggesting the presence of a degradation or stabilising signal in or near the 12AA region of ABCG1(+12).
Conclusion:
ABCG1(+12) is an isoform of ABCG1 exclusively expressed in human cells at the RNA and protein level. As ABCG1(+12) is not expressed in mice, although mouse models are widely used to elucidate the function of ABCG1, further investigations into the importance of this human ABCG1 isoform are warranted.
Related Concept Videos
Pharmacogenetics of Drug Transporters: P-Glycoprotein and Solute Carrier Transporters
Cell Specific Gene Expression
Adrenergic Receptors: β Subtype
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
ABC Transporters: Exporter

