Localization of Na+-K+ ATPases in quasi-native cell membranes.
Na(+)-K(+) ATPases have been observed and located by in situ AFM and single molecule recognition technique, topography and recognition imaging (TREC) that is a unique technique to specifically identify single protein in complex during AFM imaging. Na(+)-K(+) ATPases were well distributed in the inner leaflet of cell membranes with about 10% aggregations in total recognized proteins. The height of Na(+)-K(+) ATPases measured by AFM is in the range of 12-14 nm, which is very consistent with the cryoelectron microscopy result. The unbinding force between Na(+)-K(+) ATPases in the membrane and anti-ATPases on the AFM tip is about 80 pN with the apparent loading rate at 40 nN/s. Our results show the first visualization of an essential membrane protein, Na(+)-K(+) ATPase, in quasi-native cell membranes and may be significant to reveal the interactions between Na(+)-K(+) ATPases and other membrane proteins at the molecular level.
Jiang
Junguang
J
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, People's Republic of China.
Hao
Xian
X
Cai
Mingjun
M
Shan
Yuping
Y
Shang
Xin
X
Tang
Zhiyong
Z
Wang
Hongda
H
D040761:Biomimetic Materials / Q000737:chemistry*; D008422:Materials Testing / Q000379:methods; D008567:Membranes, Artificial; D018625:Microscopy, Atomic Force / Q000379:methods*; D015336:Molecular Probe Techniques; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis* / Q000737:chemistry* / Q000648:ultrastructure
D008567:Membranes, Artificial; D000254:Sodium-Potassium-Exchanging ATPase