Effects of calponin on isometric force and shortening velocity in permeabilized taenia coli smooth muscle.
Effects of calponin on isometric force and shortening velocity in permeabilized taenia coli smooth muscle.
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钙调蛋白对透化大肠杆菌平滑肌等长力和缩短速度的影响。
DOI：
10.1152/ajpcell.1996.270.2.c481
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Paul,RJ
中科院分区：
文献类型：
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作者：
Obara,K;Szymanski,PT;Tao,T;Paul,RJ
钙钙蛋白是一种细丝相关蛋白，在溶液中抑制肌动球蛋白腺苷三磷酸酶，并被认为可以调节平滑肌收缩性。我们使用渗透性豚鼠大肠带绦虫平滑肌来研究钙钙蛋白是否可以在更有组织的收缩系统中调节肌动蛋白-肌球蛋白的相互作用。纤维被Triton X-100和甘油渗透，允许大的大分子进入收缩装置。对于Ca2+ （6.6 μ m + 0.1 μ m钙调素）引起的收缩，鸡胗钙调蛋白（CaP）重组α -异构体呈剂量依赖性地降低了等长力（Fo）和卸载缩短速度（Vus）；1微米CaP对力的影响最小（< 10%），但将Vus降低了约50%，10微米CaP将Fo降低到对照组的27%，Vus接近零水平。为了消除钙调素与CaP结合的任何影响以及随后对肌球蛋白轻链激酶活性的抑制，我们还研究了肌球蛋白调节轻链的硫代磷酸化激活的纤维。在CaP（10微米）存在下，Fo仅受到适度抑制，保持在对照的75%左右，而Vus则降低到对照的32%。在保留与肌动蛋白结合能力的突变体（CaPcys175）中获得了类似的抑制作用。被蛋白激酶C磷酸化的CaP和标记有1,5- iaedans的CaPcys175突变体与肌动蛋白结合较差，不是有效的抑制剂。我们的研究结果表明，1)CaP对Vus（大约过桥循环率）的抑制作用强于Fo（大约激活的过桥数），2)CaP的作用与其与肌动蛋白的结合有关。因此，CaP在调节平滑肌收缩性方面的功能可能与其作为速度调制器的功能（与“锁存状态”相关）比其作为“开-关”开关的功能更密切相关。
Calponin, a thin filament-associated protein, inhibits actomyosin adenosinetriphosphatase in solution and has been suggested to modulate smooth muscle contractility. We used permeabilized guinea pig taenia coli smooth muscle to investigate whether calponin can modulate actin-myosin interaction in a more organized contractile system. Fibers were permeabilized with Triton X-100 and glycerol, which permit access of large macromolecules to the contractile apparatus. For contractures elicited by Ca2+ (6.6 microM + 0.1 microM calmodulin), the recombinant alpha-isoform of chicken gizzard calponin (CaP) decreased isometric force (Fo) and unloaded shortening velocity (Vus) in a dose-dependent manner; 1 microM CaP had minimal effects on force (< 10%) but reduced Vus by approximately 50% and 10 microM CaP reduced Fo to 27% of control and Vus to near zero levels. To eliminate any effects of the binding of calmodulin by CaP and consequent inhibition of myosin light chain kinase activity, we also studied fibers activated by thiophosphorylation of the myosin regulatory light chain. Fo was only moderately inhibited, remaining at approximately 75% of control in the presence of CaP (10 microM), whereas Vus was reduced to 32% of control. A similar inhibition was obtained with a mutant (CaPcys175) that retains the ability to bind to actin. CaP phosphorylated by protein kinase C and CaPcys175 mutant labeled with 1,5-IAEDANS, which bind actin poorly, were not effective inhibitors. Our results indicate that 1) CaP more strongly inhibits Vus (approximately cross-bridge cycle rate) than Fo (approximately number of activated cross bridges) and 2) the effects of CaP are related to its binding to actin. Thus the function of CaP in regulation of smooth muscle contractility may be more strongly related to its function as a modulator of velocity, as related to the "latch state," than as an "on-off" switch.
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Kikuko Takeuchi、Katsuhito Takahashi、Masahiro Abe、Wataru Nishida、Kunio Hiwada、Takashi Nabeya 和 Koscak Maruyama：“钙调蛋白免疫反应形式与肌动蛋白细胞骨架在血小板、成纤维细胞和血管平滑肌中的共定位。”
DOI：
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发表时间：
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作者：
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“化学剥皮”平滑肌中无负荷缩短速度对 Ca、钙调蛋白和收缩持续时间的依赖性
影响因子：
20.1
作者：
R. Paul;G. Doerman;C. Zeugner;J. C. Riiegg
通讯作者：
J. C. Riiegg
钙调蛋白磷酸化不伴随各种平滑肌的收缩。
DOI：
10.1016/0167-4889(93)90146-g
发表时间：
1993
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Bárány,M;Bárány,K
通讯作者：
Bárány,K
肌球蛋白轻链激酶抗体对化学透化平滑肌收缩性和肌球蛋白磷酸化的影响。
影响因子：
20.1
作者：
DeLanerolle,P;Strauss,JD;Felsen,R;Doerman,GE;Paul,RJ
通讯作者：
Paul,RJ
异丙肾上腺素减弱肌球蛋白磷酸化和气管肌肉的收缩。
DOI：
10.1152/jappl.1989.66.5.2017
发表时间：
1989
期刊：
Journal of applied physiology (Bethesda, Md. : 1985)
影响因子：
--
作者：
Obara,K;deLanerolle,P
通讯作者：
deLanerolle,P