Targetting of protein phosphatase 1 to the sarcoplasmic reticulum of rabbit skeletal muscle by a protein that is very similar or identical to the G subunit that directs the enzyme to glycogen.
MJ Hubbard, P Dent, C Smythe, P Cohen
Eur J Biochem | Published : 1990
The amount of protein phosphatase 1 (PP1) activity in rabbit skeletal muscle associated with membranes (predominantly sarcoplasmic reticulum) is similar to that bound to glycogen-protein particles. Membrane-vesicle-associated (sarcovesicular) PP1 can be solubilised with 0.5% Triton X-100 (but not 0.5M NaCl) and is complexed to a protein that is structurally and functionally very similar or identical to the G subunit which targets PP1 to glycogen-protein particles. This conclusion is based on immunoblotting and immunotitration experiments using two different preparations of G-subunit-specific antibodies, binding of Triton-solubilised sarcovesicular enzyme to glycogen, stimulation of phosphory..View full abstract