We have constructed a genomic DNA expression library and screened it with antibodies in order to clone the deb-1 gene from the nematode Caenorhabditis elegans. This gene encodes a protein found at the base of the muscle dense-bodies, structures which attach actin thin filaments to the sarcolemma. We report the complete sequence of the deb-1 gene, its localization on the C. elegans genetic map, and the finding that it encodes a protein with a sequence very similar to chicken vinculin. We also show that the difference in size between this nematode protein and chicken vinculin is due in part to the absence from the nematode sequence of one of the three internal repeats found in the chicken sequence.