TY - JOUR TI - In vivo dynamics of skeletal muscle Dystrophin in zebrafish embryos revealed by improved FRAP analysis AU - Bajanca, Fernanda AU - Gonzalez-Perez, Vinicio AU - Gillespie, Sean J AU - Beley, Cyriaque AU - Garcia, Luis AU - Theveneau, Eric AU - Sear, Richard P AU - Hughes, Simon M A2 - Cossu, Giulio VL - 4 PY - 2015 DA - 2015/10/13 SP - e06541 C1 - eLife 2015;4:e06541 DO - 10.7554/eLife.06541 UR - https://doi.org/10.7554/eLife.06541 AB - Dystrophin forms an essential link between sarcolemma and cytoskeleton, perturbation of which causes muscular dystrophy. We analysed Dystrophin binding dynamics in vivo for the first time. Within maturing fibres of host zebrafish embryos, our analysis reveals a pool of diffusible Dystrophin and complexes bound at the fibre membrane. Combining modelling, an improved FRAP methodology and direct semi-quantitative analysis of bleaching suggests the existence of two membrane-bound Dystrophin populations with widely differing bound lifetimes: a stable, tightly bound pool, and a dynamic bound pool with high turnover rate that exchanges with the cytoplasmic pool. The three populations were found consistently in human and zebrafish Dystrophins overexpressed in wild-type or dmdta222a/ta222a zebrafish embryos, which lack Dystrophin, and in Gt(dmd-Citrine)ct90a that express endogenously-driven tagged zebrafish Dystrophin. These results lead to a new model for Dystrophin membrane association in developing muscle, and highlight our methodology as a valuable strategy for in vivo analysis of complex protein dynamics. KW - Dystrophin KW - muscle KW - binding dynamics KW - diffusion KW - FRAP KW - software JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -