J. Biol. Chem., Vol. 262, Issue 7, 3002-3006, Mar, 1987

Differential expression of isoforms of the regulatory subunit of type II cAMP-dependent protein kinase in rat neurons, astrocytes, and oligodendrocytes

JC Stein, M Farooq, WT Norton and CS Rubin

The RII-B isoform of the regulatory subunit (R) of cAMP-dependent protein kinase II is abundantly and selectively expressed in cerebral cortex (Erlichman, J., Sarkar, D., Fleischer, N., and Rubin, C. S. (1980) J. Biol. Chem. 255, 8179-8184). In contrast to the cytosolic RII- H isoform from heart and other non-neural tissues, a substantial fraction of cerebral cortex RII-B is tightly associated with cell organelles. In order to study the cellular basis for the localization and abundance of RII-B in this complex and heterogeneous tissue, rat cerebral cortex was fractionated into highly purified populations of neurons, astrocytes, and oligodendrocytes. In neurons and astrocytes more than 80% of the total cAMP-binding activity is contributed by RII subunits, whereas the myelin-producing oligodendrocytes contain nearly equal proportions of RI (from protein kinase I) and RII. Approximately 70% of RII and RI subunits are associated with the particulate fraction in each of the three types of brain cells. The nature of the RII isoforms expressed in the cytosolic and particulate fractions of the purified brain cells was established by performing Western immunoblot and indirect immunoprecipitation analyses with selective and sensitive polyclonal antibodies directed against RII-B. Astrocytes and neurons exhibit high levels of RII-B, whereas oligodendrocytes contain the RII- H isoform. Thus, the expression of RII isoforms is not uniform among brain cells that are anatomically and developmentally related. Rather, it appears that RII-B and RII-H are expressed in a cell-specific fashion within cerebral cortex and this might reflect an RII-mediated adaptation of protein kinase II to the specialized metabolic and functional roles of neurons, astrocytes, and oligodendrocytes.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K. M. Zawadzki, Y. Hamuro, J. S. Kim, S. Garrod, D. D. Stranz, S. S. Taylor, and V. L. Woods Jr. Dissecting interdomain communication within cAPK regulatory subunit type II{beta} using enhanced amide hydrogen/deuterium exchange mass spectrometry (DXMS) Protein Sci., September 1, 2003; 12(9): 1980 - 1990. [Abstract] [Full Text] [PDF]

				Y. Dwivedi, J. S. Rao, H. S. Rizavi, J. Kotowski, R. R. Conley, R. C. Roberts, C. A. Tamminga, and G. N. Pandey Abnormal Expression and Functional Characteristics of Cyclic Adenosine Monophosphate Response Element Binding Protein in Postmortem Brain of Suicide Subjects Arch Gen Psychiatry, March 1, 2003; 60(3): 273 - 282. [Abstract] [Full Text] [PDF]

				A. Harada, J. Teng, Y. Takei, K. Oguchi, and N. Hirokawa MAP2 is required for dendrite elongation, PKA anchoring in dendrites, and proper PKA signal transduction J. Cell Biol., August 5, 2002; 158(3): 541 - 549. [Abstract] [Full Text] [PDF]

				A. P. Wiemelt, M. J. Engleka, A. F. Skorupa, and F. A. McMorris Immunochemical Visualization and Quantitation of Cyclic AMP in Single Cells J. Biol. Chem., December 12, 1997; 272(50): 31489 - 31495. [Abstract] [Full Text] [PDF]

				D. Kretzschmar, G. Hasan, S. Sharma, M. Heisenberg, and S. Benzer The Swiss Cheese Mutant Causes Glial Hyperwrapping and Brain Degeneration in Drosophila J. Neurosci., October 1, 1997; 17(19): 7425 - 7432. [Abstract] [Full Text] [PDF]

				Y. Li and C. S. Rubin Mutagenesis of the Regulatory Subunit (RIIbeta) of cAMP-dependent Protein Kinase IIbeta Reveals Hydrophobic Amino Acids That Are Essential for RIIbeta Dimerization and/or Anchoring RIIbeta to the Cytoskeleton J. Biol. Chem., January 27, 1995; 270(4): 1935 - 1944. [Abstract] [Full Text] [PDF]