Remodeling of the extracellular matrix (EM is pivotal for various biological processes, including organ morphology and development. The Caenorhabditis elegans male tail has male-specific copulatory organs, the rays and the fan. Ray morphogenesis, which involves a rapid remodeling of the ECM, is an important model of morphogenesis, although its mechanism is poorly understood. ADAMTS (a disintegrin-like and metalloproteinase with thrombospondin type I motifs) is a novel metalloproteinase family that is thought to be an important regulator for ECM remodeling during development and pathological states. We report here that a new C. elegans ADAMTS family gene,
adt-1, plays an important regulatory role in ray morphogenesis. Inactivation of the
adt-1 gene resulted in morphological changes in the rays as well as the appearance of abnormal protuberances around the rays. In addition, mating ability was remarkably impaired in
adt-1 deletion mutant males. Furthermore, we found that the green fluorescent protein reporter driven by the
adt-1 promoter was specifically expressed throughout the rays in the male tail. We hypothesize that ADT-1 controls the ray extension process via remodeling of the ECM in the cuticle.