The article describes the discovery and characterization of a novel adipose-specific gene, adipoQ, which is highly expressed in mature fat cells and regulated during adipocyte differentiation. AdipoQ encodes a polypeptide with a secretory signal sequence, a collagenous region, and a globular domain. The protein shares significant homology with subunits of complement factor C1q, collagen α1(X), and the brain-specific factor cerebellin. Expression of adipoQ is highly specific to adipose tissue in both mouse and rat, and it is significantly reduced in the adipose tissues from obese mice and humans. The study suggests that adipoQ may function as a novel signaling molecule in adipose tissue, potentially playing a role in the regulation of energy balance and metabolic functions.The article describes the discovery and characterization of a novel adipose-specific gene, adipoQ, which is highly expressed in mature fat cells and regulated during adipocyte differentiation. AdipoQ encodes a polypeptide with a secretory signal sequence, a collagenous region, and a globular domain. The protein shares significant homology with subunits of complement factor C1q, collagen α1(X), and the brain-specific factor cerebellin. Expression of adipoQ is highly specific to adipose tissue in both mouse and rat, and it is significantly reduced in the adipose tissues from obese mice and humans. The study suggests that adipoQ may function as a novel signaling molecule in adipose tissue, potentially playing a role in the regulation of energy balance and metabolic functions.