Abstract
A Ca2+-insensitive myosin light chain kinase was prepared and used in experiments with skinned gizzard fibers. In the absence of Ca2+, this kinase activated isometric force development. The force development was associated with phosphorylation of the 20,000-dalton myosin light chains and addition of Ca2+ did not activate the fibers further. Pretreatment of the fibers with Ca2+-insensitive myosin light chain kinase and adenosine 5'-O-(3-thiotriphosphate) in the absence of Ca2+ caused thiophosphorylation of the light chains and, on the addition of ATP, an activation of isometric tension was observed. The subsequent addition of Ca2+ did not increase force development. A comparison of Ca2+-activated tension in the skinned gizzard muscle fibers with Ca2+-insensitive myosin light chain kinase-activated tension suggests that the phosphorylation of the myosin light chains is the dominant factor in the development of tension in smooth muscle.
| Original language | English |
|---|---|
| Pages (from-to) | 5987-5990 |
| Number of pages | 4 |
| Journal | Journal of Biological Chemistry |
| Volume | 257 |
| Issue number | 11 |
| State | Published - Jun 10 1982 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Biochemistry
Cite this
Phosphorylation-dependent activated tension in skinned gizzard muscle fibers in the absence of Ca2+. / Walsh, M. P.; Bridenbaugh, R.; Hartshorne, D. J.; Kerrick, W. Glenn.
In: Journal of Biological Chemistry, Vol. 257, No. 11, 10.06.1982, p. 5987-5990.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Phosphorylation-dependent activated tension in skinned gizzard muscle fibers in the absence of Ca2+.
AU - Walsh, M. P.
AU - Bridenbaugh, R.
AU - Hartshorne, D. J.
AU - Kerrick, W. Glenn
PY - 1982/6/10
Y1 - 1982/6/10
N2 - A Ca2+-insensitive myosin light chain kinase was prepared and used in experiments with skinned gizzard fibers. In the absence of Ca2+, this kinase activated isometric force development. The force development was associated with phosphorylation of the 20,000-dalton myosin light chains and addition of Ca2+ did not activate the fibers further. Pretreatment of the fibers with Ca2+-insensitive myosin light chain kinase and adenosine 5'-O-(3-thiotriphosphate) in the absence of Ca2+ caused thiophosphorylation of the light chains and, on the addition of ATP, an activation of isometric tension was observed. The subsequent addition of Ca2+ did not increase force development. A comparison of Ca2+-activated tension in the skinned gizzard muscle fibers with Ca2+-insensitive myosin light chain kinase-activated tension suggests that the phosphorylation of the myosin light chains is the dominant factor in the development of tension in smooth muscle.
AB - A Ca2+-insensitive myosin light chain kinase was prepared and used in experiments with skinned gizzard fibers. In the absence of Ca2+, this kinase activated isometric force development. The force development was associated with phosphorylation of the 20,000-dalton myosin light chains and addition of Ca2+ did not activate the fibers further. Pretreatment of the fibers with Ca2+-insensitive myosin light chain kinase and adenosine 5'-O-(3-thiotriphosphate) in the absence of Ca2+ caused thiophosphorylation of the light chains and, on the addition of ATP, an activation of isometric tension was observed. The subsequent addition of Ca2+ did not increase force development. A comparison of Ca2+-activated tension in the skinned gizzard muscle fibers with Ca2+-insensitive myosin light chain kinase-activated tension suggests that the phosphorylation of the myosin light chains is the dominant factor in the development of tension in smooth muscle.
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M3 - Article
C2 - 6896202
AN - SCOPUS:0020479095
VL - 257
SP - 5987
EP - 5990
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 11
ER -