GLC8 is a regulatory subunit of protein phosphatase 1 (Glc7p). This protein involved in glycogen metabolism and chromosome segregation, proposed to regulate Glc7p activity via conformational alteration; ortholog of the mammalian protein phosphatase inhibitor 2. Under normal conditions, Glc8p activates Glc7p, but when Glc8p is over produced, it may also inhibit Glc7p function. Glc8p is activated upon phosphoylation by Pho85p complexed with four cyclins (Pcl6p, Pcl7p, Pcl8p, or Pcl10p). Recombinant yeast GLC8 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.