Figure 2.

Ca²⁺-ATPase activity and immunodetection of SERCA1 and sarcoplasmic reticulum protein markers in microsomal fractions enriched in sarcoplasmic reticulum membranes from PMT affected Romagnola cattle. (A) The Ca²⁺-ATPase activity was determined by a spectrophotometric enzyme-coupled assay at optimum pCa (pCa 5) as described in Methods. Control values were obtained from different preparations of microsomes obtained from four unaffected animals of the same age. Data are expressed as the relative expression with respect to control muscle and are mean + SD. (B) Sarcoplasmic reticulum microsomal fractions from unaffected and PMT affected calves were separated by 5-10% SDS-PAGE and blotted onto nitrocellulose. Blots were incubated with the four indicated antibodies.