Traditional and emerging roles for the SLC9 Na+/H+ exchangers

@article{Fuster2013TraditionalAE,
  title={Traditional and emerging roles for the SLC9 Na+/H+ exchangers},
  author={Daniel G. Fuster and R. Todd Alexander},
  journal={Pfl{\"u}gers Archiv - European Journal of Physiology},
  year={2013},
  volume={466},
  pages={61-76}
}
The SLC9 gene family encodes Na+/H+ exchangers (NHEs). These transmembrane proteins transport ions across lipid bilayers in a diverse array of species from prokaryotes to eukaryotes, including plants, fungi, and animals. They utilize the electrochemical gradient of one ion to transport another ion against its electrochemical gradient. Currently, 13 evolutionarily conserved NHE isoforms are known in mammals [22, 46, 128]. The SLC9 gene family (solute carrier classification of transporters: www… 

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NHE8 is expressed in the proximal tubule, where it may contribute to apical membrane ion transport, and is the mammalian ortholog of this ancient invertebrate isoform.

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The Epithelial Sodium-Hydrogen Antiporter Na+/H+ Exchanger 3 Accumulates and Is Functional in Recycling Endosomes*

Results indicate that NHE3 is present and active in recycling endosomes, and modulation of vesicular traffic could contribute to the regulation of Na+ reabsorption across epithelia.

Na+/H+ exchanger isoform 6 (NHE6/SLC9A6) is involved in clathrin-dependent endocytosis of transferrin.

Microscopic analysis revealed that, at 2 min after the onset of endocytosis, colocalization of NHE6, clathrin, and transferrin was observed, which suggests that NHE 6 was localized to endocyTotic,Clathrin-coated vesicles.

SLC9/NHE gene family, a plasma membrane and organellar family of Na⁺/H⁺ exchangers.

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Immunochemical characterization of Na+/H+exchanger isoform NHE4.

It is concluded that NHE4 is a 65- to 70-kDa protein with a broad tissue distribution that was expressed most abundantly in stomach and in multiple additional epithelial and nonepithelial rat tissues including skeletal muscle, heart, kidney, uterus, and liver.
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