Characterization of DHP binding protein in crayfish striated muscle.
The dihydropyridine calcium channel blocker, [3H]PN 200-110, binds specifically also to crayfish muscle membranes, though with a binding capacity smaller than that measured with rabbit or human skeletal muscle membranes. [3H]PN 200-110 binding proteins from the crayfish T-tubules were solubilized and purified on WGA Sepharose or extracted from gel. The purified protein has a molecular mass of approximately 190 kDa under nonreducing conditions and was able to transport calcium after reconstitution. Polyclonal antibodies against crayfish T-tubules enriched with purified DHP-binding protein were shown to bind to DHP-binding protein from both the crayfish and the rabbit skeletal muscle, although not with the same intensity. Electron microscopy showed the presence of ovoid particles. Our results suggest that a voltage-dependent calcium channel may be present in crayfish skeletal muscle, which is homological with the L-type calcium channel in rabbit skeletal muscle.
Krizanova
O
O
Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava.
Novotova
M
M
Zachar
J
J
D000818:Animals; D003400:Astacoidea / Q000378:metabolism*; D001692:Biological Transport; D015220:Calcium Channels / Q000378:metabolism; D004586:Electrophoresis / Q000379:methods; D015151:Immunoblotting; D008854:Microscopy, Electron; D009132:Muscles / Q000378:metabolism*; D011978:Receptors, Nicotinic / Q000302:isolation & purification*
D015220:Calcium Channels; D011978:Receptors, Nicotinic