| Method |
optical single transporter recording (OSTR), for optically recording the activity of single transporters in membrane patches. Cells or organelles are firmly attached to isoporous filters, and the transport across membrane patches spanning filter pores is measured by confocal laser scanning microphotolysis (SCAMP) (Wedekind et al., 1994), the amalgamation of microphotolysis and laser scanning microscopy. Because the transport rate constant of the single NPC was known, the equivalent length of the channel could be also determined and was found to be 40-50 nm (mean 44.5 nm). |