Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 2002 Mar 15;362(Pt 3):533–537. doi: 10.1042/0264-6021:3620533

A dual-specificity isoform of the protein kinase inhibitor PKI produced by alternate gene splicing.

Priyadarsini Kumar 1, Donal A Walsh 1
PMCID: PMC1222415  PMID: 11879178

Abstract

We have previously shown that the protein kinase inhibitor beta (PKIbeta) form of the cAMP-dependent protein kinase inhibitor exists in multiple isoforms, some of which are specific inhibitors of the cAMP-dependent protein kinase, whereas others also inhibit the cGMP-dependent enzyme [Kumar, Van Patten and Walsh (1997), J. Biol. Chem. 272, 20011-20020]. We have now demonstrated that the switch from a cAMP-dependent protein kinase (PKA)-specific inhibitor to one with dual specificity arises as a consequence of alternate gene splicing. We have confirmed using bacterially produced pure protein that a single inhibitor species has dual specificity for both PKA and cGMP-dependent protein kinase (PKG), inhibiting each with very high and closely similar inhibitory potencies. The gene splicing converted a protein with 70 amino acids into one of 109 amino acids, and did not change the inhibitory potency to PKA, but changed it from a protein that had no detectable PKG inhibitory activity to one that now inhibited PKG in the nanomolar range.

Full Text

The Full Text of this article is available as a PDF (174.5 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Glass D. B., Cheng H. C., Kemp B. E., Walsh D. A. Differential and common recognition of the catalytic sites of the cGMP-dependent and cAMP-dependent protein kinases by inhibitory peptides derived from the heat-stable inhibitor protein. J Biol Chem. 1986 Sep 15;261(26):12166–12171. [PubMed] [Google Scholar]
  2. Glass D. B., Cheng H. C., Mende-Mueller L., Reed J., Walsh D. A. Primary structural determinants essential for potent inhibition of cAMP-dependent protein kinase by inhibitory peptides corresponding to the active portion of the heat-stable inhibitor protein. J Biol Chem. 1989 May 25;264(15):8802–8810. [PubMed] [Google Scholar]
  3. Glass D. B., Feller M. J., Levin L. R., Walsh D. A. Structural basis for the low affinities of yeast cAMP-dependent and mammalian cGMP-dependent protein kinases for protein kinase inhibitor peptides. Biochemistry. 1992 Feb 18;31(6):1728–1734. doi: 10.1021/bi00121a021. [DOI] [PubMed] [Google Scholar]
  4. Glass D. B., Krebs E. G. Protein phosphorylation catalyzed by cyclic AMP-dependent and cyclic GMP-dependent protein kinases. Annu Rev Pharmacol Toxicol. 1980;20:363–388. doi: 10.1146/annurev.pa.20.040180.002051. [DOI] [PubMed] [Google Scholar]
  5. Hanks S. K., Quinn A. M. Protein kinase catalytic domain sequence database: identification of conserved features of primary structure and classification of family members. Methods Enzymol. 1991;200:38–62. doi: 10.1016/0076-6879(91)00126-h. [DOI] [PubMed] [Google Scholar]
  6. Kemp B. E., Pearson R. B. Intrasteric regulation of protein kinases and phosphatases. Biochim Biophys Acta. 1991 Aug 13;1094(1):67–76. doi: 10.1016/0167-4889(91)90027-u. [DOI] [PubMed] [Google Scholar]
  7. Knighton D. R., Zheng J. H., Ten Eyck L. F., Xuong N. H., Taylor S. S., Sowadski J. M. Structure of a peptide inhibitor bound to the catalytic subunit of cyclic adenosine monophosphate-dependent protein kinase. Science. 1991 Jul 26;253(5018):414–420. doi: 10.1126/science.1862343. [DOI] [PubMed] [Google Scholar]
  8. Kumar P., Van Patten S. M., Walsh D. A. Multiplicity of the beta form of the cAMP-dependent protein kinase inhibitor protein generated by post-translational modification and alternate translational initiation. J Biol Chem. 1997 Aug 8;272(32):20011–20020. doi: 10.1074/jbc.272.32.20011. [DOI] [PubMed] [Google Scholar]
  9. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  10. Reed J., De Ropp J. S., Trewhella J., Glass D. B., Liddle W. K., Bradbury E. M., Kinzel V., Walsh D. A. Conformational analysis of PKI(5-22)amide, the active inhibitory fragment of the inhibitor protein of the cyclic AMP-dependent protein kinase. Biochem J. 1989 Dec 1;264(2):371–380. doi: 10.1042/bj2640371. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Scarpetta M. A., Uhler M. D. Evidence for two additional isoforms of the endogenous protein kinase inhibitor of cAMP-dependent protein kinase in mouse. J Biol Chem. 1993 May 25;268(15):10927–10931. [PubMed] [Google Scholar]
  12. Slice L. W., Taylor S. S. Expression of the catalytic subunit of cAMP-dependent protein kinase in Escherichia coli. J Biol Chem. 1989 Dec 15;264(35):20940–20946. [PubMed] [Google Scholar]
  13. Studier F. W., Rosenberg A. H., Dunn J. J., Dubendorff J. W. Use of T7 RNA polymerase to direct expression of cloned genes. Methods Enzymol. 1990;185:60–89. doi: 10.1016/0076-6879(90)85008-c. [DOI] [PubMed] [Google Scholar]
  14. Szmigielski A., Guidotti A., Costa E. Endogenous protein kinase inhibitors. Purification, characterization, and distribution in different tissues. J Biol Chem. 1977 Jun 10;252(11):3848–3853. [PubMed] [Google Scholar]
  15. Van Patten S. M., Howard P., Walsh D. A., Maurer R. A. The alpha- and beta-isoforms of the inhibitor protein of the 3',5'-cyclic adenosine monophosphate-dependent protein kinase: characteristics and tissue- and developmental-specific expression. Mol Endocrinol. 1992 Dec;6(12):2114–2122. doi: 10.1210/mend.6.12.1491692. [DOI] [PubMed] [Google Scholar]
  16. Van Patten S. M., Ng D. C., Th'ng J. P., Angelos K. L., Smith A. J., Walsh D. A. Molecular cloning of a rat testis form of the inhibitor protein of cAMP-dependent protein kinase. Proc Natl Acad Sci U S A. 1991 Jun 15;88(12):5383–5387. doi: 10.1073/pnas.88.12.5383. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Whitehouse S., Walsh D. A. Inhibitor protein of the cAMP-dependent protein kinase: characteristics and purification. Methods Enzymol. 1983;99:80–93. doi: 10.1016/0076-6879(83)99044-4. [DOI] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES