title: Localization of Na+-K+ ATPases in quasi-native cell membranes.
abstract: 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.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, People's Republic of China.
authors.forename: Junguang
authors.initials: J
authors.lastname: Jiang
authors.forename: Xian
authors.initials: X
authors.lastname: Hao
authors.forename: Mingjun
authors.initials: M
authors.lastname: Cai
authors.forename: Yuping
authors.initials: Y
authors.lastname: Shan
authors.forename: Xin
authors.initials: X
authors.lastname: Shang
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Tang
authors.forename: Hongda
authors.initials: H
authors.lastname: Wang
mesh_terms: 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
chemical_list: D008567:Membranes, Artificial; D000254:Sodium-Potassium-Exchanging ATPase