Structural Biology

Similar but Not the Same

Science's STKE  25 May 2004:
Vol. 2004, Issue 234, pp. tw190
DOI: 10.1126/stke.2342004TW190

Resistin and adiponectin are two serum proteins secreted by adipocytes. Adiponectin exists in low- and high-molecular-weight forms (LMW and HMW), and the relative amount of the HMW species correlates with systemic responsiveness to insulin and with thiazolidinedione-induced improvement in animal models of obesity-associated insulin resistance. Patel et al. describe the crystal structure of resistin, which bears no sequence similarity to adiponectin, yet also exists in a small form consisting of three monomers intertwined via a coiled coil and in a larger hexamer formed by the tail-to-tail association of two trimers. A further intriguing similarity is that the smaller, trimeric form of resistin can act as a potent antagonist of insulin effects on rat liver.

S. D. Patel, M. W. Rajala, L. Rossetti, P. E. Scherer, L. Shapiro, Disulfide-dependent multimeric assembly of resistin family hormones. Science 304, 1154-1158 (2004). [Abstract] [Full Text]