Official websites use. Share sensitive information only on official, secure websites. Address correspondence to: Kathrin Gieseler gieseler cgmc. In Caenorhabditis elegans , mutations of the dystrophin homologue, dys-1 , produce a peculiar behavioral phenotype hyperactivity and a tendency to hypercontract.
In a sensitized genetic background, dys-1 mutations also lead to muscle necrosis. The dyc-1 gene was previously identified in a genetic screen because its mutation leads to the same phenotype as dys-1, suggesting that the two genes are functionally linked. Here, we report the detailed characterization of the dyc-1 gene. Isoform-specific RNAi experiments show that the absence of the muscle isoform, and not that of the neuronal isoform, is responsible for the dyc-1 mutant phenotype.
In the sarcomere, the DYC-1 protein is localized at the edges of the dense body, the nematode muscle adhesion structure where actin filaments are anchored and linked to the sarcolemma. ZYX-1 localizes at dense bodies and M-lines as well as in the nucleus of C. The DYC-1 protein possesses a highly conserved 19 amino acid sequence, which is involved in the interaction with ZYX-1 and which is sufficient for addressing DYC-1 to the dense body.
Altogether our findings indicate that DYC-1 may be involved in dense body function and stability. This, taken together with the functional link between the C. As the dense body shares functional similarity with both the vertebrate Z-disk and the costamere, we therefore postulate that disruption of muscle cell adhesion structures might be the primary event of muscle degeneration occurring in the absence of dystrophin, in C.
Duchenne muscular dystrophy DMD is due to mutations in the dystrophin gene. This gene encodes a amino acid protein, which is localized under the sarcolemma of skeletal and cardiac muscles Koenig et al. In skeletal muscle, dystrophin is mainly localized at a rib-like lattice called the costamere, which is a specific muscle adhesion complex linking the Z-disk to the sarcolemma Porter et al. Dystrophin is not required for costameric organization, because costameres can form in the dystrophin-deficient mdx mouse Porter et al.
