Villaz M, Ronjat M, Garrigos M, Dupont Y
Tissue Cell. 1987;19(1):135-43. doi: 10.1016/0040-8166(87)90064-4.
The striated remotor muscle of the lobster antenna has an extraordinarily profuse sarcoplasmic reticulum as shown by electron microscopy. Gel electrophoresis reveals a simple protein composition in which the Ca2+-ATPase predominates. Vesicles of sarcoplasmic reticulum (SR) from this remotor are shown to operate Ca2+ binding, Ca2+ transport, and Ca2+-activated hydrolysis of ATP with an usual efficiency (2 Ca2+ transported per ATP hydrolysed, 4 mumol ATP hydrolysed/mg protein/min). Skinned fiber experiments were performed. They indicate behaviour of the remotor expected from observations by EM and gel electrophoresis: contraction of low maximal intensity under Ca2+ excitation, long internal diffusion time due to the large volume of SR to be crossed, and large Ca2+ content released in a caffeine-sensitive manner.
