Scientific publications

Shared apical sorting of anion exchanger isoforms AE2a, AE2b1, and AE2b2 in primary hepatocytes

Aranda V, Martínez I, Melero S, Lecanda J, Banales JM, Prieto J, Medina JF.
Laboratory of Molecular Genetics, Division of Gene Therapy and Hepatology, University Hospital/School of Medicine, Center for Applied Medical Research, University of Navarra, Pamplona, Spain.

Magazine: Biochemical and Biophysical Research Communications

Date: Jul 1, 2004


AE2 (SLC4A2) is the member of the Na(+)-independent anion exchanger (AE) family putatively involved in the secretion of bicarbonate to bile. In humans, three variants of AE2 mRNA have been described: the full-length transcript AE2a (expressed from the upstream promoter in most tissues), and alternative transcripts AE2b(1) and AE2b(2) (driven from alternate promoter sequences in a tissue-restricted manner, mainly in liver and kidney).

These transcripts would result in AE protein isoforms with short N-terminal differences. To ascertain their translation, functionality, and membrane sorting, we constructed expression vectors encoding each AE2 isoform fused to GFP at the C-terminus. Transfected HEK293 cells showed expression of functional GFP-tagged AE2 proteins, all three isoforms displaying comparable AE activities. Primary rat hepatocytes transfected with expression vectors and repolarized in a collagen-sandwich configuration showed a microtubule-dependent apical sorting of each AE2 isoform. This shared apical sorting is liver-cell specific, as sorting of AE2 isoforms was basolateral in control experiments on polarized kidney MDCK cells.

Hepatocytic apical targeting of AE2 isoforms suggests that they all may participate in the canalicular secretion of bicarbonate to bile.

CITATION  Biochem Biophys Res Commun. 2004 Jul 2;319(3):1040-6

you maybe interested


The Clínica is the greater private hospital with technological equipment of Spain, all in a single center.

Imagen de un PET, tecnología de vanguardia en la Clínica Universidad de Navarra


The professionals of the Clínica perform continuous research and training, always to the benefit of the patient.

Imagen profesionales de la Clínica Universidad de Navarra


Learn why we are different from other healthcare centers. Quality, speed, comfort and results.

Imagen del edificio de la Clínica Universidad de Navarra