Open AccessFGF signaling directs myotube guidance by regulating Rac activity
Author(s) -
Shuo Yang,
Allison Weske,
Yingqiu Du,
Juliana M. Valera,
Aaron N Johnson
Publication year - 2020
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.754
H-Index - 325
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.183624
Subject(s) - myogenesis , biology , microbiology and biotechnology , fibroblast growth factor , cytoskeleton , signal transduction , actin , myocyte , genetics , receptor , cell
Nascent myotubes undergo a dramatic morphological transformation during myogenesis in which the myotubes elongate over several cell diameters and choose the correct muscle attachment sites. Although this process of myotube guidance is essential to pattern the musculoskeletal system, the mechanisms that control myotube guidance remain poorly understood. Using transcriptomics, we found that components of the Fibroblast Growth Factor (FGF) signaling pathway were enriched in nascent myotubes in Drosophila embryos. Null mutations in the FGF receptor heartless (htl), or its ligands, caused significant myotube guidance defects. The FGF ligand Pyramus is expressed broadly in the ectoderm and ectopic Pyramus expression disrupted muscle patterning. Mechanistically, Htl regulates the activity of Rho/Rac GTPases in nascent myotubes and effects changes in the actin cytoskeleton. FGF signals are thus essential regulators of myotube guidance that act through cytoskeletal regulatory proteins to pattern the musculoskeletal system.