Slow muscles guide fast myocyte fusion to ensure robust myotome formation despite the high spatiotemporal stochasticity of fusion events

• DOI: 10.1016/j.devcel.2022.08.002
• Publication Date: 2022-08-25T14:52:30Z
• Authors: Mario A. Mendieta...; Sunandan Dhar; Boon Heng Ng; Rachna Narayanan; Jorge J.Y. Lee; Hui Ting Ong; Pearlyn Jia Ying Toh; Adrian Röllin; Sudipto Roy; Timothy E. Saunders
• Keywords: Myotome; Cell fusion; Fusion mechanism

Skeletal myogenesis is dynamic, and it involves cell-shape changes together with cell fusion rearrangements. However, the final muscle arrangement highly organized striated fibers. By combining live imaging quantitative analyses, we dissected fast-twitch myocyte within zebrafish myotome in toto. We found a strong mediolateral bias timing; however, at cellular scale, there was heterogeneity shape relationship between initial position of fast myocytes resulting partners. show that expression fusogen myomaker permissive, but not instructive, determining spatiotemporal pattern. Rather, observed close coordination slow rearrangements fusion. In mutants lack fibers, pattern substantially noisier. propose model which muscles guide by funneling them together, enhancing probability. Thus, despite being stochastic, robust structure emerges tissue scale.