Autor: |
Paul, Jose K., Nettikadan, Saju R., Ganjeizadeh, Mehdi, Yamaguchi, Mamoru, Takeyasu, Kunio |
Zdroj: |
FEBS Letters; January 1994, Vol. 346 Issue: 2 p289-294, 6p |
Abstrakt: |
Ion channels and pumps in cell membranes consist of multiple transmembrane segments that are thought to be critical for transport of ions. Channel structures constituted by these transmembrane segments are characteristic of ion channels, whereas such structures have not been identified in ion pumps until now. By applying atomic force microscopy on Na +,K +-ATPase molecules in canine kidney membranes under tapping mode, we identified a hollow in the protein with a characteristic internal diameter of 6–20A˚and an external diameter of 20–55A˚depending upon treatment conditions. This hollow may be interpreted as a channel-like conformation of Na +,K +-ATPase. In the regions where the proteins were absent, lipid head structures with 2A˚width and 6A˚length were imaged in an orthorhombic lattice. |
Databáze: |
Supplemental Index |
Externí odkaz: |
|