TESTSYSTEMS FOR TRANSPORT PROTEINS

摘要

A cholesterol loaded insect cell membrane preparation comprising an increased cholesterol level as compared to the physiological cholesterol level of the same type of insect cell membrane, the insect cell membrane preparation comprising an ABC transporter protein having an increased substrate transport activity as compared to the substrate transport activity of the ABC transporter protein if present in the same type of insect cell membrane having a physiological cholesterol level, is new. Independent claims are: (1) a cholesterol loaded insect cell preparation comprising an increased cholesterol level as compared to the physiological cholesterol level of the membrane of the same type of insect cell, the insect cell preparation comprising an ABC transporter protein having an increased substrate transport activity as compared to the substrate transport activity of the ABC transporter protein if present in the membrane of the same type of insect cell having a physiological cholesterol level; (2) a reagent kit for assessing activity of an ABC transporter protein, the kit comprising: (a) the preparation above, and/or (b) means for expressing the ABC transporter in insect cells and means for loading the insect cells with cholesterol and/or a cholesterol analogue, and optionally means for preparing a membrane preparation from the insect cells, and (c) if desired, any of the following: substrates of the ABC transporter protein, ATP, cholesterol or cholesterol analogues, buffers, reagents, controls, inhibitors, or activators of the ABC transporter protein; (3) a method for manufacturing an insect cell preparation or an insect cell membrane preparation; (4) an insect cell preparation or an insect cell membrane preparation comprising an increased cholesterol level as compared to the physiological cholesterol level of insect cell membranes and an ABC transporter protein of increased substrate transport activity as compared the substrate transport activity of the ABC transporter protein in an insect cell membrane having physiological cholesterol content, where the insect cell preparation or the insect cell membrane preparation is obtainable by the method above; (5) an assay method for studying interaction of a compound and an ABC transporter protein by assessing activity of the ABC transporter protein; and (6) an assay method for testing simultaneous interaction of at least two compounds and an ABC transporter protein by assessing activity of the transporter protein.