RELM alpha, also known as found in inflammatory zone (FIZZ1) belongs to the RELM1/FIZZ family of cysteine-rich secretory proteins and shares homology with resistin. It is abundantly expressed in white adipose tissue but not in preadipocytes, nor 3T3-L1 adipocytes. RELM alpha expression is also detected in bronchial epithelium and type II pneumocytes. RELM beta (resistin-like molecule beta/FIZZ2) is a cysteine-rich protein expressed specifically in the intestine. It is highly homologous to resistin and RELM alpha. RELM beta and resistin contain eleven cysteines with identical spacing which mediate formation of disulfide-linked homodimers. They further associate into trimers and hexamers.