Has a high affinity for collagen. Affects nematode body morphology and mobility. Essential for C.elegans development and muscle function. The cysteine-rich region could have protease inhibitory activity or may provide the framework for a protein binding module. Probable role in skeletal morphogenesis. In or around the basement membrane. Expressed by body wall and sex muscle cells. Probable association with basement membranes. First expressed in unhatched larvae; continuous throughout subsequent larval stages and in adults. Belongs to the SPARC family.