Article

Expression of the Abca-subfamily of genes in Abcc6-/- mice--upregulation of Abca4.

Department of Dermatology and Cutaneous Biology, Jefferson Medical College, and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA.
Experimental Dermatology (impact factor: 3.54). 03/2011; 20(5):452-4. DOI:10.1111/j.1600-0625.2010.01240.x
Source: PubMed

ABSTRACT Pseudoxanthoma elasticum (PXE), a heritable multi-system disorder, is caused by mutations in the ABCC6 gene primarily expressed in the liver. Recent analysis of cultured fibroblasts from patients with PXE has suggested compensatory alterations in the expression of the ABCA-subfamily of genes. We have now determined by quantitative RT-PCR the level of expression of Abca-family of genes in a mouse model of PXE developed by targeted ablation of Abcc6. The results indicated variable levels of mRNA for different Abca genes in the liver; however, only one of them, Abca4, was significantly, ∼6.5-fold, upregulated in the Abcc6(-/-) mice in comparison with wild-type mice. In the same mice, Abca4 was not upregulated in the eyes or the kidney, suggesting that the upregulation of Abca4 in the liver is a tissue-specific compensatory consequence of the 'knock-out' of Abcc6.

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Keywords

'knock-out'
 
Abca-family
 
ABCA-subfamily
 
Abca4
 
ABCC6 gene
 
ablation
 
compensatory alterations
 
cultured fibroblasts
 
different Abca genes
 
eyes
 
genes
 
heritable multi-system disorder
 
Pseudoxanthoma elasticum
 
PXE
 
quantitative RT-PCR
 
Recent analysis
 
tissue-specific compensatory consequence
 
variable levels
 

Qiaoli Li