B
ilitranslocase (TC 2.A.65.1.1) is a plasma membrane transporter
expressed in the gastro-intestinal epithelium (luminal side), the
liver and kidney (vascular side) (1) and in the vascular endothelium (2).
It transports bilirubin, flavonoids and other organic anions. By using
specific anti-sequence bilitranslocase antibodies targeting extracellular
epitopes critical for the carrier function, we can investigate both
the tissue and cellular localisation of the protein and its function
in absorption and tissue distribution of flavonoids, by a system of in
vitro methods featured by increasing structural complexity: i) plasma
membrane vesicles, ii) cell cultures, iii) tissue fragments, and iv)
isolated organs. The best example of implementation of this chain
of in vitro methods is the cardiovascular system, where consistent
observations were obtained throughout the chain. It can be concluded
that the first method, i.e. a bilitranslocase-specific functional assay
(3) in membrane vesicles where potential ligands (competitive and
non-competitive inhibitors) are identified, yields data predictive of
bilitranslocase function in organs. This approach can be helpful for
exploiting bilitranslocase as a membrane transporter in drug targeting
and development.
1 Passamonti S, Terdoslavich M, Franca R, Vanzo A, Tramer F, Braidot
E, et al. Curr Drug Metab. 2009 May;10(4):369-94.
2 Maestro A, Terdoslavich M, Vanzo A, Kuku A, Tramer F, Nicolin V, et
al.. Cardiovasc Res. 2009 Aug 25.
3 Passamonti S, Tramer F, Petrussa E, Braidot E, Vianello A. In: FettNeto AG, editor. Plant Secondary Metabolism Engineering Methods
and Applications. Totowa, NJ: Humana Press Inc.; 2010.
