Fig. 1

Co-immunoprecipitation evidences for a multiprotein complex involved in excitation-transcription coupling. a Characterization of triad-enriched fractions derived from rat or mouse muscles. Several proteins were detected by immunoblot: dihydropyridine receptor (DHPR), ryanodine receptor 1 (RyR1), sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA), heat shock protein 70 (HSP70), pannexin 1 (Panx1), P2Y₂ receptor (P2Y₂R) and caveolin-3 (Cav3). b, c Several protein components for the excitation-transcription machinery co-precipitate both in mouse adult muscle triad preparation (b) and in rat myotube extracts (c). The voltage sensor (DHPR), the ATP-release channel (Panx1), and a receptor for extracellular ATP (P2Y₂R) co-precipitate suggesting a multiprotein complex. The scaffold protein dystrophin (Dys) co-precipitate with DHPR, Panx1, and P2Y₂R. Protein immunodetection in the whole lysate and pre-clearing samples are shown as positive and negative controls, respectively (b, c)