First Author | Codina J | Year | 2005 |
Journal | Am J Physiol Cell Physiol | Volume | 288 |
Issue | 6 | Pages | C1279-86 |
PubMed ID | 15647390 | Mgi Jnum | J:101236 |
Mgi Id | MGI:3603490 | Doi | 10.1152/ajpcell.00463.2004 |
Citation | Codina J, et al. (2005) CD63 interacts with the carboxy terminus of the colonic H+-K+-ATPase to increase plasma membrane localization and 86Rb+ uptake. Am J Physiol Cell Physiol 288(6):C1279-86 |
abstractText | The carboxy terminus (CT) of the colonic H(+)-K(+)-ATPase is required for stable assembly with the beta-subunit, translocation to the plasma membrane, and efficient function of the transporter. To identify protein-protein interactions involved in the localization and function of HKalpha(2), we selected 84 amino acids in the CT of the alpha-subunit of mouse colonic H(+)-K(+)-ATPase (CT-HKalpha(2)) as the bait in a yeast two-hybrid screen of a mouse kidney cDNA library. The longest identified clone was CD63. To characterize the interaction of CT-HKalpha(2) with CD63, recombinant CT-HKalpha(2) and CD63 were synthesized in vitro and incubated, and complexes were immunoprecipitated. CT-HKalpha(2) protein (but not CT-HKalpha(1)) coprecipitated with CD63, confirming stable assembly of HKalpha(2) with CD63. In HEK-293 transfected with HKalpha(2) plus beta(1)-Na(+)-K(+)-ATPase, suppression of CD63 by RNA interference increased cell surface expression of HKalpha(2)/NKbeta(1) and (86)Rb(+) uptake. These studies demonstrate that CD63 participates in the regulation of the abundance of the HKalpha(2)-NKbeta(1) complex in the cell membrane. |