It is intended to provide a protein participating in the regulation of sugar production, a polynucleotide encoding the same, a method of screening a compound participating in the regulation of sugar production and a drug for treating or preventing diabetes which contains the compound participating in the regulation of sugar production. A polynucleotide encoding a protein specifically binding to a substance WF00144 is found out from rat liver cells and thus a protein participating in the regulation of sugar production and a polynucleotide encoding the same are provided. Moreover, a method and a substance relating to a method of treating and preventing diabetes are found out and thus a method of treating diabetes relating to the regulation of sugar production relating to the method of treating and preventing diabetes is provided.
