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Fig. 3
Origin of the Repair Membrane
(A and B) Schematic representation of the two possible sources of the sarcolemmal resealing membrane. (A) Random plasma membrane fragments, decorated with mCherry-CAAX (magenta) or Dysf (green) could provide substrate for membrane repair. (B) Specific Dysf-enriched membrane domains exist for resealing of lesions.
(C) FRAP experiment with mOrange1-tagged DysfC and mCherry-CAAX show comparable kinetics in undamaged myofibers.
(D) The TM domain of Dysf (DysfC) accumulates rapidly at the site of lesion. Much slower or no accumulation was observed for mCherry-CAAX, mTFP1-SNAP23 and Cav3-mTFP1.
(E) Coexpression of mTFP1-DysfC and mCherry-CAAX. In contrast to mTFP1-DysfC (green), mCherry-CAAX (magenta) does not accumulate in the lesion.
(F) Visualization of Lamp1-mTFP1, mTFP1-Rab1a, mTFP1-Rab5a, mTFP1-Rab6a, mTFP1-Rab7, mTFP1-Rab12, mTFP1-Rab27a, and mTFP1-Stx4 localization (green) in uninjured and injured cells. No significant relocation of the studied vesicle markers could be observed. mCherry-CAAX marks the cell membrane in magenta. White arrow indicates damaged sarcolemma.
Scale bars represent 3 μm (E) and 4 μm (F). See also Figures S2 and S3.
Reprinted from Developmental Cell, 22(3), Roostalu, U., and Strähle, U., In Vivo imaging of molecular interactions at damaged sarcolemma, 515-529, Copyright (2012) with permission from Elsevier. Full text @ Dev. Cell