Mechanism of Catch Force: Tethering of Thick and Thin Filaments by Twitchin
Figure 9
Relationship between the fractional decrease in force caused by phosphorylation of twitchin and the total force (/) before twitchin phosphorylation in permeabilized ABRM. Data for individual muscles are shown as the following: pCa 4.5, + (⊡); pCa 5, control (), 5 mM (), 25 mM (), blebbistatin 1.25–25 M (); pCa 5.7, control (■), 5 mM (□); pCa 6, control (, ▲), 5 mM (○), BDM 10 mM (∆), TFP 200 M (⊙); pCa 6.3 (♦), 5 mM (); pCa 7, (▾). Mean SE ( = 16) for catch force remaining 10 minutes (), 20 minutes () after switch from pCa 6 to pCa 8. The line is a least squares quadratic fit to the data. = 20 C. Reproduced from [98] with permission.