Resistance to insulin characterizes type 2 diabetes, the most common form of diabetes. There is a strong link between type 2 diabetes and obesity, as most patients tend to be obese. Thiozolidinediones (TZDs), a new class of anti-diabetic drugs, enhances target-tissue sensitivity to insulin. A screen of genes down regulated by TZD in adipocyte led to the discovery of a new protein hormone called resistin (for resistance to insulin). Resistin, specifically produced and secreted by adipocyte, is present at elevated levels in the blood of obese animals, and is down regulated by fasting and anti-diabetic drugs. Antibody to resistin stimulated glucose uptake and improved insulin sensitivity in obese mice. Some other protein related to resistin has been called resistin-related molecules (RELM-alpha and beta). Resistin family of proteins was also identified as proteins (FIZZ1-3, for Found in Inflammatory zone) involved in allergy and inflammation. RELM-beta/FIZZ2 (prepeptides: mouse 105 aa; human 11 aa ~45-65% identity with FIZZ1 and 2) is highly related to resistin at the C-terminus region. Its expression is most abundant in colon (proximal and distal colon) but not in white adipose tissue. In mouse, RELM-beta is also detected at low levels in cecum and ileum. In min mouse (mouse model for human familial adenomatosus polyposis), RELM-beta expression was markedly increased in tumors immediately adjacent to normal tissue. The purified protein is a disulfide linked homodimer of ~19kD consisting of two 89aa chains.