The effects of caldesmon extraction on mechanical properties of skinned smooth muscle fibre preparations
(1996) In Pflügers Archiv 432(2). p.241-247- Abstract
- The role of caldesmon in the regulation of smooth muscle contraction was investigated in chemically skinned smooth muscle fibres from the guinea-pig taenia coli. A 19-kDa C-terminal fragment of caldesmon gave a minor (<5%) reduction of force in fully thiophosphorylated fibres, but reduced force by about 50% at intermediate activation levels without affecting the level of light chain phosphorylation. An extraction procedure was developed using incubation in solutions containing high Mg2+ concentrations. Protein analysis revealed a selective decrease in the amount of caldesmon in the fibres. Maximal active force per cross-sectional area was unaffected. The Ca2+ dependence of active force was shifted towards lower Ca2+ concentrations and... (More)
- The role of caldesmon in the regulation of smooth muscle contraction was investigated in chemically skinned smooth muscle fibres from the guinea-pig taenia coli. A 19-kDa C-terminal fragment of caldesmon gave a minor (<5%) reduction of force in fully thiophosphorylated fibres, but reduced force by about 50% at intermediate activation levels without affecting the level of light chain phosphorylation. An extraction procedure was developed using incubation in solutions containing high Mg2+ concentrations. Protein analysis revealed a selective decrease in the amount of caldesmon in the fibres. Maximal active force per cross-sectional area was unaffected. The Ca2+ dependence of active force was shifted towards lower Ca2+ concentrations and became less steep. The effects of extraction of caldesmon could in part be reversed by incubation in a solution containing purified caldesmon. The results are consistent with the hypothesis that caldesmon in smooth muscle thin filaments inhibits force generation and plays a role in regulating cooperative attachment of cross-bridges at sub-maximal levels of activation in smooth muscle. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1110909
- author
- Malmqvist, Ulf LU ; Arner, A ; Makuch, R and Dabrowska, R
- organization
- publishing date
- 1996
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Skinned smooth muscle, Caldesmon, 19-kDa fragment, Calcium sensitivity
- in
- Pflügers Archiv
- volume
- 432
- issue
- 2
- pages
- 241 - 247
- publisher
- Springer
- external identifiers
-
- pmid:8662300
- scopus:0029957346
- ISSN
- 0031-6768
- DOI
- 10.1007/s004240050130
- language
- English
- LU publication?
- yes
- id
- 18d2527a-6aac-4742-aa7e-7b8cf9bc8a97 (old id 1110909)
- date added to LUP
- 2016-04-01 17:01:42
- date last changed
- 2022-01-28 23:50:13
@article{18d2527a-6aac-4742-aa7e-7b8cf9bc8a97, abstract = {{The role of caldesmon in the regulation of smooth muscle contraction was investigated in chemically skinned smooth muscle fibres from the guinea-pig taenia coli. A 19-kDa C-terminal fragment of caldesmon gave a minor (<5%) reduction of force in fully thiophosphorylated fibres, but reduced force by about 50% at intermediate activation levels without affecting the level of light chain phosphorylation. An extraction procedure was developed using incubation in solutions containing high Mg2+ concentrations. Protein analysis revealed a selective decrease in the amount of caldesmon in the fibres. Maximal active force per cross-sectional area was unaffected. The Ca2+ dependence of active force was shifted towards lower Ca2+ concentrations and became less steep. The effects of extraction of caldesmon could in part be reversed by incubation in a solution containing purified caldesmon. The results are consistent with the hypothesis that caldesmon in smooth muscle thin filaments inhibits force generation and plays a role in regulating cooperative attachment of cross-bridges at sub-maximal levels of activation in smooth muscle.}}, author = {{Malmqvist, Ulf and Arner, A and Makuch, R and Dabrowska, R}}, issn = {{0031-6768}}, keywords = {{Skinned smooth muscle; Caldesmon; 19-kDa fragment; Calcium sensitivity}}, language = {{eng}}, number = {{2}}, pages = {{241--247}}, publisher = {{Springer}}, series = {{Pflügers Archiv}}, title = {{The effects of caldesmon extraction on mechanical properties of skinned smooth muscle fibre preparations}}, url = {{http://dx.doi.org/10.1007/s004240050130}}, doi = {{10.1007/s004240050130}}, volume = {{432}}, year = {{1996}}, }