Codina, MartaGutiérrez Fruitós, JoaquínKao, Joseph P. Y.Du, Shao JunLi, Junling2018-10-012018-10-012010-01-011932-6203https://hdl.handle.net/2445/124984Background Myofibrillogenesis requires the correct folding and assembly of sarcomeric proteins into highly organized sarcomeres. Heat shock protein 90α1 (Hsp90α1) has been implicated as a myosin chaperone that plays a key role in myofibrillogenesis. Knockdown or mutation of hsp90α1 resulted in complete disorganization of thick and thin filaments and M- and Z-line structures. It is not clear whether the disorganization of these sarcomeric structures is due to a direct effect from loss of Hsp90α1 function or indirectly through the disorganization of myosin thick filaments. Methodology/Principal Findings In this study, we carried out a loss-of-function analysis of myosin thick filaments via gene-specific knockdown or using a myosin ATPase inhibitor BTS (N-benzyl-p-toluene sulphonamide) in zebrafish embryos. We demonstrated that knockdown of myosin heavy chain 1 (myhc1) resulted in sarcomeric defects in the thick and thin filaments and defective alignment of Z-lines. Similarly, treating zebrafish embryos with BTS disrupted thick and thin filament organization, with little effect on the M- and Z-lines. In contrast, loss of Hsp90α1 function completely disrupted all sarcomeric structures including both thick and thin filaments as well as the M- and Z-lines. Conclusion/Significance Together, these studies indicate that the hsp90α1 mutant phenotype is not simply due to disruption of myosin folding and assembly, suggesting that Hsp90α1 may play a role in the assembly and organization of other sarcomeric structures.9 p.application/pdfengcc-by (c) Codina, M. et al., 2010http://creativecommons.org/licenses/by/3.0/esPeix zebraContracció muscularProteïnesZebra danioMuscle contractionProteinsinfo:eu-repo/semantics/article5730982018-10-01info:eu-repo/semantics/openAccess