Actions downstream of cGMP/PKG can reverse PKC-mediated phosphorylation of CPI-17 and Ca2+ sensitization in smooth muscle.
(2004) In Journal of Biological Chemistry 279(24). p.28998-29003- Abstract
- Ca2+ sensitivity of smooth muscle contraction is modulated by several systems converging on myosin light chain phosphatase (MLCP). Rho-Rho kinase is considered to inhibit MLCP via phosphorylation, whereas protein kinase C (PKC) induced sensitization has been shown to be dependent on phosphorylation of the inhibitory protein CPI-17. We have explored the interaction of cGMP-dependent protein kinase (PKG) with Ca2+ sensitization pathways using permeabilized mouse smooth muscle. Three conditions giving ~50% of maximal active force were compared in small intestinal preparations: 1) Ca2+-activated unsensitized muscle (pCa 5.9 with Rho kinase inhibitor Y27632); 2) Rho-Rho kinase-sensitized muscle (pCa 6.1 with guanosine... (More)
- Ca2+ sensitivity of smooth muscle contraction is modulated by several systems converging on myosin light chain phosphatase (MLCP). Rho-Rho kinase is considered to inhibit MLCP via phosphorylation, whereas protein kinase C (PKC) induced sensitization has been shown to be dependent on phosphorylation of the inhibitory protein CPI-17. We have explored the interaction of cGMP-dependent protein kinase (PKG) with Ca2+ sensitization pathways using permeabilized mouse smooth muscle. Three conditions giving ~50% of maximal active force were compared in small intestinal preparations: 1) Ca2+-activated unsensitized muscle (pCa 5.9 with Rho kinase inhibitor Y27632); 2) Rho-Rho kinase-sensitized muscle (pCa 6.1 with guanosine 5'-3-O-(thio)triphosphate); and 3) PKC-sensitized muscle (pCa 6.0 with Y27632 and PKC activator phorbol 12,13-dibutyrate). 8-Br-cGMP relaxed the sensitized muscles but had marginal effects on unsensitized preparations, showing that PKG reverses both PKC and Rho-mediated Ca2+ sensitization. CPI-17 was present in permeabilized intestinal tissue. In PKC-sensitized preparations, CPI-17 phosphorylation decreased in response to 8-Br-cGMP. The rate of PKC-mediated phosphorylation in the presence of the MLCP inhibitor microcystin-LR was not influenced by 8-Br-cGMP. PKC-induced Ca2+ sensitization also was reversed in vascular smooth muscle tissues (portal vein and femoral artery). We conclude that actions downstream of cGMP/PKG can reverse PKC-mediated phosphorylation of CPI-17 and Ca2+ sensitization in smooth muscle. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/123642
- author
- Bonnevier, Johan LU and Arner, Anders LU
- organization
- publishing date
- 2004
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Biological Chemistry
- volume
- 279
- issue
- 24
- pages
- 28998 - 29003
- publisher
- American Society for Biochemistry and Molecular Biology
- external identifiers
-
- wos:000222445300022
- scopus:3142675244
- ISSN
- 1083-351X
- DOI
- 10.1074/jbc.M404259200
- language
- English
- LU publication?
- yes
- id
- 445f15e6-4ca1-4668-a570-f846a7568d5e (old id 123642)
- date added to LUP
- 2016-04-01 12:08:35
- date last changed
- 2022-01-26 23:25:14
@article{445f15e6-4ca1-4668-a570-f846a7568d5e, abstract = {{Ca2+ sensitivity of smooth muscle contraction is modulated by several systems converging on myosin light chain phosphatase (MLCP). Rho-Rho kinase is considered to inhibit MLCP via phosphorylation, whereas protein kinase C (PKC) induced sensitization has been shown to be dependent on phosphorylation of the inhibitory protein CPI-17. We have explored the interaction of cGMP-dependent protein kinase (PKG) with Ca2+ sensitization pathways using permeabilized mouse smooth muscle. Three conditions giving ~50% of maximal active force were compared in small intestinal preparations: 1) Ca2+-activated unsensitized muscle (pCa 5.9 with Rho kinase inhibitor Y27632); 2) Rho-Rho kinase-sensitized muscle (pCa 6.1 with guanosine 5'-3-O-(thio)triphosphate); and 3) PKC-sensitized muscle (pCa 6.0 with Y27632 and PKC activator phorbol 12,13-dibutyrate). 8-Br-cGMP relaxed the sensitized muscles but had marginal effects on unsensitized preparations, showing that PKG reverses both PKC and Rho-mediated Ca2+ sensitization. CPI-17 was present in permeabilized intestinal tissue. In PKC-sensitized preparations, CPI-17 phosphorylation decreased in response to 8-Br-cGMP. The rate of PKC-mediated phosphorylation in the presence of the MLCP inhibitor microcystin-LR was not influenced by 8-Br-cGMP. PKC-induced Ca2+ sensitization also was reversed in vascular smooth muscle tissues (portal vein and femoral artery). We conclude that actions downstream of cGMP/PKG can reverse PKC-mediated phosphorylation of CPI-17 and Ca2+ sensitization in smooth muscle.}}, author = {{Bonnevier, Johan and Arner, Anders}}, issn = {{1083-351X}}, language = {{eng}}, number = {{24}}, pages = {{28998--29003}}, publisher = {{American Society for Biochemistry and Molecular Biology}}, series = {{Journal of Biological Chemistry}}, title = {{Actions downstream of cGMP/PKG can reverse PKC-mediated phosphorylation of CPI-17 and Ca2+ sensitization in smooth muscle.}}, url = {{http://dx.doi.org/10.1074/jbc.M404259200}}, doi = {{10.1074/jbc.M404259200}}, volume = {{279}}, year = {{2004}}, }