Apparent precursor of a secreted, cationic, proline- and cysteine-rich peptide that contains Cys-Pro-Xaa repeats. Unlike cryptdin, the proposed mature peptide region lacks the structural motif characteristic of defensins. It may have microbicidal activities. Small bowel, spleen, colon, kidney, liver, stomach and femur marrow. Accumulates to high levels in intestinal crypt epithelium during postnatal development. Belongs to the alpha-defensin family.