PortaCellTec biosciences GmbH

Family SLCO

The physiological, pharmaceutical and pathological role of human Organic Anion Transporting Polypeptides  (OATPs) of the SLCO Family

General overview

OATP transporters are found in the animal kingdom only and are encoded by genes of the solute carrier organic anion transporter (SLCO) superfamily, which in humans includes 11 members. Based on hydropathy analyses, all OATPs contain 12 transmembrane domains, but this has not been proven experimentally for any OATP. The mechanism of substrate transport via OATP transporters is not completely understood, though a recent computational study suggested that OATPs translocate their substrates through a central, positively charged pore in a so-called rocker-switch type of mechanism. OATP-mediated transport is independent of sodium, chloride and potassium gradients, membrane potential and ATP levels.

Driving force and mechanism of drug transport by OATPs
The cellular uptake via OATP transporters is believed to occur by electroneutral exchange, in which the cellular uptake of organic anions is coupled to the efflux of neutralizing anions such as bicarbonate, glutathione or glutathione-S-conjugates. However, the nature of the neutralizing ion remains unknown for human OATPs.



New validated products:

  • mNtcp
  • mOct1


3rd German Pharm-Tox Summit
Göttingen, Germany
26 February - 1 March 2018

Saarbrücken, Germany
8 March 2018


AAPS Workshop
Virginia, USA
16 - 18 April 2018


20th Barrier- and

Bad Herrenalb, Germany
7 - 9 May 2018

Greifswalder Transporttage 2018
Greifswald, Germany
October 2018


Guidance for Industry (FDA and EMA)