We have isolated, sequenced, mapped and disrupted a novel gene, CCC1, from Saccharomyces cerevisiae. This gene displays non-allelic complementation of the Ca(2+)-sensitive phenotype conferred by the csg1 mutation. The ability of this gene, in two copies per cell, to reverse the csg1 defect suggests it may have a role in regulating Ca2+ homeostasis. The sequence of CCC1 indicates that it encodes a 322 amino acid, membrane-associated protein. The CCC1 gene is located on the right arm of chromosome XII.