RRC ID 62183
Author Arimochi J, Ohashi-Kobayashi A, Maeda M.
Title Interaction of Mat-8 (FXYD-3) with Na+/K+-ATPase in colorectal cancer cells.
Journal Biol Pharm Bull
Abstract Mat-8 was fused with a Myc-tag or green fluorescent protein at its carboxyl terminus, and then expressed in Chinese hamster ovary K1 cells. Determination of the cellular localization of the tagged proteins suggested that they were localized on the intracellular membrane, being not only detected around the nuclear envelope but also partly overlapping with markers for endosomes and Golgi bodies. However, Mat-8 with the Myc-tag was detected on the plasma membrane as well as the intracellular membrane, when it was expressed in colorectal cancer cells. The membrane fraction of the cancer cells was solubilized and immuno-precipitated with an antibody for the Myc-tag. Western-blotting analysis demonstrated that the Na+/K+-ATPase alpha subunit was present in the precipitate. Furthermore, the immuno-precipitate obtained with an antibody for the Na+/K+-ATPase alpha subunit reacted with that for the Myc-tag. These results suggested that Mat-8 could be associated with Na+/K+-ATPase similar to other FXYD family members. The Gly41-->Arg mutation in the transmembrane region of Mat-8 inhibited its association with the Na+/K+-ATPase alpha subunit and localization on the plasma membrane, whereas the Cys44-->Ala or Cys49-->Ala substitution did not. Thus the conserved Gly41 residue in the transmembrane domain could be indispensable for localization of Mat-8 on the cell surface.
Volume 30(4)
Pages 648-54
Published 2007-4-1
DOI 10.1248/bpb.30.648
PII JST.JSTAGE/bpb/30.648
PMID 17409496
MeSH Amino Acid Motifs Amino Acid Sequence Amino Acid Substitution Animals Arginine / metabolism Blotting, Western CHO Cells Caco-2 Cells Colorectal Neoplasms / enzymology* Colorectal Neoplasms / pathology Conserved Sequence Cricetinae Cricetulus Fluorescent Dyes Green Fluorescent Proteins / metabolism Humans Indoles Membrane Proteins / chemistry Membrane Proteins / genetics Membrane Proteins / metabolism* Mice Microscopy, Fluorescence Molecular Sequence Data Neoplasm Proteins / chemistry Neoplasm Proteins / genetics Neoplasm Proteins / metabolism* Precipitin Tests Protein Structure, Tertiary Recombinant Fusion Proteins / chemistry Recombinant Fusion Proteins / metabolism Sequence Homology, Amino Acid Sodium-Potassium-Exchanging ATPase / metabolism*
IF 1.863
Human and Animal Cells CACO-2(RCB0988)