An RNAi based screen in Drosophila larvae identifies fascin as a regulator of myoblast fusion and myotendinous junction structure.

Background: A strength of Drosophila as a model system is its utility as a tool to screen for novel regulators of various functional and developmental processes. However, the utility of Drosophila as a screening tool is dependent on the speed and simplicity of the assay used.

Methods: Here, we use larval locomotion as an assay to identify novel regulators of skeletal muscle function.

Aplip1, the homolog of JIP1, regulates myonuclear positioning and muscle stability.

During muscle development, myonuclei undergo a complex set of movements that result in evenly spaced nuclei throughout the muscle cell. In , two separate pools of Kinesin and Dynein work in synchrony to drive this process. However, how these two pools are specified is not known.

Emery-Dreifuss muscular dystrophy-linked genes and centronuclear myopathy-linked genes regulate myonuclear movement by distinct mechanisms.

Muscle cells are a syncytium in which the many nuclei are positioned to maximize the distance between adjacent nuclei. Although mispositioned nuclei are correlated with many muscle disorders, it is not known whether this common phenotype is the result of a common mechanism. To answer this question, we disrupted the expression of genes linked to Emery-Dreifuss muscular dystrophy (EDMD) and centronuclear myopathy (CNM) in and evaluated the position of the nuclei.