Structural and functional analysis of the Na+/H+ exchanger.
Emily R Slepkov1, Jan K Rainey, Brian D Sykes
1Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2H7.
The Biochemical Journal
|January 11, 2007
Summary
The Na+/H+ exchanger 1 (NHE1) regulates cell pH and is vital in many physiological processes. This review details NHE1
Area of Science:
- Biochemistry
- Cell Biology
- Physiology
Background:
- Mammalian Na+/H+ exchanger 1 (NHE1) is an integral membrane protein regulating intracellular pH.
- NHE1 plays roles in cell volume control, cytoskeletal organization, heart disease, and cancer.
- NHE1 has two domains: a membrane transport domain and a cytoplasmic regulatory domain.
Purpose of the Study:
- To review current knowledge on the functional and structural aspects of NHE1.
- To discuss identified amino acid residues crucial for NHE function.
- To explore progress in elucidating NHE structures.
Main Methods:
- Review of existing literature on NHE1.
- Analysis of structural data for NHE1 transmembrane segments.
- Comparison of NHE1 structure with bacterial Na+/H+ antiporter (NhaA).
Main Results:
- Recent studies identified key amino acid residues for NHE function.
- The structure of a single transmembrane segment of NHE1 has been determined.
- The bacterial NhaA structure reveals similarities with transmembrane segment IV of NHE1, despite low sequence homology.
Conclusions:
- Understanding NHE1 function and structure is advancing.
- Structural similarities between NHE1 and NhaA offer insights into transport mechanisms.
- Further experiments are needed to fully elucidate NHE1 transport and regulation.
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