The Journal of Membrane Biology

, Volume 213, Issue 3, pp 187–193 | Cite as

C-Terminal Determinants of Kir4.2 Channel Expression

  • Wade L. Pearson
  • Serguei N. Skatchkov
  • Misty J. Eaton
  • Colin G. Nichols
Article

Abstract

Inward rectifier potassium (Kir) channels serve important functional and modulatory roles in a wide variety of cells. While the activity of several members of this channel family are tightly regulated by intracellular messengers such as adenosine triphosphate, G proteins, protein kinases and pH, other members are tonically active and activity is controlled only by the expression level of the protein. In a number of Kir channels, sequence motifs have been identified which determine how effectively the channel is trafficked to and from the plasma membrane. In this report, we identify a number of trafficking determinants in the Kir4.2 channel. Using mutational analysis, we found that truncation of the C terminus of the protein increased current density in Xenopus oocytes, although multiple mutations of the C terminus had no effect on current density. Instead, mutation of a unique region of the channel significantly increased current density. Selective mutation of a putative tyrosine phosphorylation site within this region mimicked the increase in current, suggesting that tyrosine phosphorylation of the protein increases channel retrieval from the membrane (or prevents trafficking to the membrane). Mutation of a previously identified trafficking determinant, K110N, also caused an increase in current density, and combining these mutations caused a multiplicative increase in current, suggesting that these two mutations increase current by independent mechanisms. These data demonstrate novel determinants of Kir4.2 channel expression.

Keywords

Endoplasmic reticulum Oocyte Tyrosine phosphorylation Trafficking 

Notes

Acknowledgement

This work was supported by National Institutes of Health grants DK02773 (to W. L. P.) and NS048201 (to M. J. E.). We are indebted to Dr. Stan Misler for support and advice during experiments and for comments on the manuscript.

References

  1. Bond C.T., Pessia M., Xia X.M., Lagrutta A., Kavanaugh M.P., Adelman J.P. 1994. Cloning and expression of a family of inward rectifier potassium channels. Receptors Channels 2:183–191PubMedGoogle Scholar
  2. Cohen N.A., Brenman J.E., Snyder S.H., Bredt D.S. 1996. Binding of the inward rectifier K+ channel Kir2.3 to PSD-95 is regulated by protein kinase A phosphorylation. Neuron 17:759–767PubMedCrossRefGoogle Scholar
  3. Derst C., Wischmeyer E., Preisig-Muller R., Spauschus A., Konrad M., Hensen P., Jeck N., Seyberth H.W., Daut J., Karschin A. 1998. A hyperprostaglandin E syndrome mutation in Kir1.1 (renal outer medullary potassium) channels reveals a crucial residue for channel function in Kir1.3 channels. J. Biol. Chem. 273:23884–23891PubMedCrossRefGoogle Scholar
  4. Flagg T.P., Yoo D., Sciortino C.M., Tate M., Romero M.F., Welling P.A. 2002. Molecular mechanism of a COOH-terminal gating determinant in the ROMK channel revealed by a Bartter’s disease mutation. J. Physiol. 544:351–362PubMedCrossRefGoogle Scholar
  5. Frindt G., Zhou H., Sackin H., Palmer L.G. 1998. Dissociation of K channel density and ROMK mRNA in rat cortical collecting tubule during K adaptation. Am. J. Physiol. 274:F525–F531PubMedGoogle Scholar
  6. Horio Y., Hibino H., Inanobe A., Yamada M., Ishii M., Tada Y., Satoh E., Hata Y., Takai Y., Kurachi Y. 1997. Clustering and enhanced activity of an inwardly rectifying potassium channel, Kir4.1, by an anchoring protein, PSD-95/SAP90. J. Biol. Chem. 272:12885–12888PubMedCrossRefGoogle Scholar
  7. Inagaki N., Gonoi T., Clement J.P.T., Namba N., Inazawa J., Gonzalez G., Aguilar-Bryan L., Seino S., Bryan J. 1995. Reconstitution of I KATP: An inward rectifier subunit plus the sulfonylurea receptor. Science 270:1166–1170PubMedCrossRefGoogle Scholar
  8. Ishii M., Horio Y., Tada Y., Hibino H., Inanobe A., Ito M., Yamada M., Gotow T., Uchiyama Y., Kurachi Y. 1997. Expression and clustered distribution of an inwardly rectifying potassium channel, KAB-2/Kir4.1, on mammalian retinal Muller cell membrane: Their regulation by insulin and laminin signals. J. Neurosci. 17:7725–7735PubMedGoogle Scholar
  9. Krapivinsky G., Gordon E.A., Wickman K., Velimirovic B., Krapivinsky L., Clapham D.E. 1995. The G-protein-gated atrial K+ channel IKACh is a heteromultimer of two inwardly rectifying K+-channel proteins. Nature 374:135–141PubMedCrossRefGoogle Scholar
  10. Kurschner C., Mermelstein P.G., Holden W.T., Surmeier D.J. 1998. CIPP, a novel multivalent PDZ domain protein, selectively interacts with Kir4.0 family members, NMDA receptor subunits, neurexins, and neuroligins. Mol. Cell. Neurosci. 11:161–172PubMedCrossRefGoogle Scholar
  11. Leipziger J., MacGregor G.G., Cooper G.J., Xu J., Hebert S.C., Giebisch G. 2000. PKA site mutations of ROMK2 channels shift the pH dependence to more alkaline values. Am. J. Physiol. 279:F919–F926Google Scholar
  12. Lin D., Sterling H., Lerea K.M., Giebisch G., Wang W.H. 2002a. Protein kinase C (PKC)-induced phosphorylation of ROMK1 is essential for the surface expression of ROMK1 channels. J. Biol. Chem. 277:44278–44284CrossRefGoogle Scholar
  13. Lin D.H., Sterling H., Lerea K.M., Welling P., Jin L., Giebisch G., Wang W.H. 2002b. K depletion increases protein tyrosine kinase-mediated phosphorylation of ROMK. Am. J. Physiol. 283:F671–F677Google Scholar
  14. Ma D., Zerangue N., Lin Y.F., Collins A., Yu M., Jan Y.N., Jan L.Y. 2001. Role of ER export signals in controlling surface potassium channel numbers. Science 291:316–319PubMedCrossRefGoogle Scholar
  15. Ma D., Zerangue N., Raab-Graham K., Fried S.R., Jan Y.N., Jan L.Y. 2002. Diverse trafficking patterns due to multiple traffic motifs in G protein-activated inwardly rectifying potassium channels from brain and heart. Neuron 33:715–729PubMedCrossRefGoogle Scholar
  16. Moral Z., Dong K., Wei Y., Sterling H., Deng H., Ali S., Gu R., Huang X.Y., Hebert S.C., Giebisch G., Wang W.H. 2001. Regulation of ROMK1 channels by protein-tyrosine kinase and -tyrosine phosphatase. J. Biol. Chem. 276:7156–7163PubMedCrossRefGoogle Scholar
  17. Nishida M., MacKinnon R. 2002. Structural basis of inward rectification. Cytoplasmic pore of the G protein-gated inward rectifier GIRK1 at 1.8 A resolution. Cell 111:957–965PubMedCrossRefGoogle Scholar
  18. Palmada M., Embark H.M., Wyatt A.W., Bohmer C., Lang F. 2003. Negative charge at the consensus sequence for the serum- and glucocorticoid-inducible kinase, SGK1, determines pH sensitivity of the renal outer medullary K+ channel, ROMK1. Biochem. Biophys. Res. Commun. 307:967–972PubMedCrossRefGoogle Scholar
  19. Palmer L.G., Antonian L., Frindt G. 1994. Regulation of apical K and Na channels and Na/K pumps in rat cortical collecting tubule by dietary K. J. Gen. Physiol. 104:693–710PubMedCrossRefGoogle Scholar
  20. Pearson W.L., Dourado M., Schreiber M., Salkoff L., Nichols C.G. 1999. Expression of a functional Kir4 family inward rectifier K+ channel from a gene cloned from mouse liver. J. Physiol. 514:639–653PubMedCrossRefGoogle Scholar
  21. Pessia M., Imbrici P., D’Adamo M.C., Salvatore L., Tucker S.J. 2001. Differential pH sensitivity of Kir4.1 and Kir4.2 potassium channels and their modulation by heteropolymerisation with Kir5.1. J. Physiol. 532:359–367PubMedCrossRefGoogle Scholar
  22. Pessia M., Tucker S.J., Lee K., Bond C.T., Adelman J.P. 1996. Subunit positional effects revealed by novel heteromeric inwardly rectifying K+ channels. EMBO J. 15:2980–2987PubMedGoogle Scholar
  23. Pond L., Kuhn L.A., Teyton L., Schutze M.P., Tainer J.A., Jackson M.R., Peterson P.A. 1995. A role for acidic residues in di-leucine motif-based targeting to the endocytic pathway. J. Biol. Chem. 270:19989–19997PubMedCrossRefGoogle Scholar
  24. Schulte U., Hahn H., Konrad M., Jeck N., Derst C., Wild K., Weidemann S., Ruppersberg J.P., Fakler B., Ludwig J. 1999. pH gating of ROMK (Kir1.1) channels: Control by an Arg-Lys-Arg triad disrupted in antenatal Bartter syndrome. Proc. Natl. Acad. Sci. USA 96:15298–15303PubMedCrossRefGoogle Scholar
  25. Shuck M.E., Piser T.M., Bock J.H., Slightom J.L., Lee K.S., Bienkowski M.J. 1997. Cloning and characterization of two K+ inward rectifier (Kir) 1.1 potassium channel homologs from human kidney (Kir1.2 and Kir1.3). J. Biol. Chem. 272:586–593PubMedCrossRefGoogle Scholar
  26. Stanfield P.R., Davies N.W., Shelton P.A., Sutcliffe M.J., Khan I.A., Brammar W.J., Conley E.C. 1994. A single aspartate residue is involved in both intrinsic gating and blockage by Mg2+ of the inward rectifier, IRK1. J. Physiol. 478:1–6PubMedGoogle Scholar
  27. Sterling H., Lin D.H., Gu R.M., Dong K., Hebert S.C., Wang W.H. 2002. Inhibition of protein-tyrosine phosphatase stimulates the dynamin-dependent endocytosis of ROMK1. J. Biol. Chem. 277:4317–4323PubMedCrossRefGoogle Scholar
  28. Tanemoto M., Fujita A., Higashi K., Kurachi Y. 2002. PSD-95 mediates formation of a functional homomeric Kir5.1 channel in the brain. Neuron 34:387–397PubMedCrossRefGoogle Scholar
  29. Tucker S.J., Gribble F.M., Zhao C., Trapp S., Ashcroft F.M. 1997. Truncation of Kir6.2 produces ATP-sensitive K+ channels in the absence of the sulphonylurea receptor. Nature 387:179–183PubMedCrossRefGoogle Scholar
  30. Wald H., Garty H., Palmer L.G., Popovtzer M.M. 1998. Differential regulation of ROMK expression in kidney cortex and medulla by aldosterone and potassium. Am. J. Physiol. 275:F239–F245PubMedGoogle Scholar
  31. Wang W.H., Lin D.H., Sterling H. 2002. Regulation of ROMK channels by protein tyrosine kinase and tyrosine phosphatase. Trends Cardiovasc. Med. 12:138–142PubMedCrossRefGoogle Scholar
  32. Wei Y., Bloom P., Lin D., Gu R., Wang W.H. 2001. Effect of dietary K intake on apical small-conductance K channel in CCD: Role of protein tyrosine kinase. Am. J. Physiol. 281:F206–F212Google Scholar
  33. Yan F., Lin C.W., Weisiger E., Cartier E.A., Taschenberger G., Shyng S.L. 2004. Sulfonylureas correct trafficking defects of ATP-sensitive potassium channels caused by mutations in the sulfonylurea receptor. J. Biol. Chem. 279:11096–11105PubMedCrossRefGoogle Scholar
  34. Zerangue N., Malan M.J., Fried S.R., Dazin P.F., Jan Y.N., Jan L.Y., Schwappach B. 2001. Analysis of endoplasmic reticulum trafficking signals by combinatorial screening in mammalian cells. Proc. Natl. Acad. Sci. USA 98:2431–2436PubMedCrossRefGoogle Scholar
  35. Zerangue N., Schwappach B., Jan Y.N., Jan L.Y. 1999. A new ER trafficking signal regulates the subunit stoichiometry of plasma membrane KATP channels. Neuron 22:537–548PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Wade L. Pearson
    • 1
  • Serguei N. Skatchkov
    • 2
    • 3
  • Misty J. Eaton
    • 2
  • Colin G. Nichols
    • 1
  1. 1.Department of Cell Biology and PhysiologyWashington University School of MedicineSt. Louis
  2. 2.Department of BiochemistryUniversidad Central del Caribe School of MedicineBayamon
  3. 3.Department of PhysiologyUniversidad Central del Caribe School of MedicineBayamon

Personalised recommendations