RELMbeta (Resistin-like molecule beta/FIZZ2) is a disulfide-linked, homodimeric protein expressed in the epithelium of the colon and small bowel. The biological functions of RELMbeta, and its molecular targets, are not fully known, but it has been suggested that it plays a regulatory role during inflammation, and may also act to establish links among adipose tissue, the intestine and the liver. Interestingly, the molecular structure of RELMbeta is highly homologous to that of the adipose-derived cytokines, resistin and RELMalpha. These proteins share a highly conserved C-terminal domain, characterized by 10 cysteine residues with a unique spacing motif of C-X11-C-X8-C-X-C-X3-C-X10-C-X-C-X-C-X9-C-C. Recombinant Murine RELMbeta is an 18.0 kDa protein, consisting of two identical 83 amino acid polypeptide chains linked by a single disulfide bond.