Human NESP55 polypeptides, polynucleotides and uses thereof

The present invention relates to polypeptides, polynucleotides and uses thereof in screening and in medicine. A substantially pure polypeptide (human NESP55) comprising the amino acid sequenceor a variant, fragment, fusion or derivative thereof, or a fusion of a said variant or fragment or derivative, wherein the polypeptide variant has an amino acid sequence which has at least 90% identity with the amino acid sequence given above.NESP55 or fragments thereof may be useful in medicine for the treatment of obesity.