Fig. 6. Western blots of crayfish and lobster opener muscle fibres probed with an antibody to troponin-T (TnT) . Fast (F), slow-twitch (S1) and slow-tonic (S2) fibres from lobster cutter claw closer, crusher claw closer and superficial abdominal muscles are provided for reference (lanes a–c, respectively); the reference fibres used for the lobster blot (A) were different from the reference fibres used for the crayfish blots (B,C). In lobster, only the proximal fibres (S2) in the leg opener muscle expressed TnT1 (A, lanes d, e). The proximal and distal fibres (S2) expressed variable amounts of TnT1 (arrow) in the crayfish leg opener (B, lanes d, e, h, i) and crayfish claw opener muscles (B, lanes d, e, g), with higher levels of TnT1 in proximal fibres. The central region of crayfish opener muscles (B, lanes f, g; C, lane f) and the central and distal regions of lobster leg opener (A, lanes f–h) contained S1 fibres. The positions of molecular mass standards are indicated on the left.