Figure 10.

Overlay assays of adult skeletal muscle extracts with GST-4.1R-10 kDa variants. (A) Skeletal muscle homogenates were overlaid with GST-4.1R-10 kDa polypeptides that included or skipped exon 16 and control GST protein, as indicated above the lanes, followed by immunoblotting with anti-GST antibodies. A highly specific and strong association between 4.1R-10 kDa polypeptides and myosin heavy chain, α-actin, and skeletal tropomyosin was detected (immunoreactive proteins are denoted by double arrows, single arrows, and arrowheads, respectively). An additional band of ∼110 kDa was also observed that remains unidentified (X-protein). (B) Western blot analysis verified the identity of the immunoreactive bands after probing three replica blots with anti-myosin (MF20-ab), anti-actin (JLA20-ab), and anti-tropomyosin (CH1-ab) antibodies.