Protein Stain-EZ J Phosphoprotein Staining Kit: Protein phosphorylaon and dephosphorylaon play significant regulatory roles in a variety of cellular processes such as normal and abnormal cell growth, cell death and secreon. The Phosphoprotein Staining Kit specifically stains phosphorylated proteins directly on gels. Staining is achieved by first hydrolyzing the phosphoprotein phosphoester linkage using 0.5 N NaOH in the presence of calcium ions. The gel containing the newly formed insoluble calcium phosphate is then treated with ammonium molybdate in dilute nitric acid. The resultant insoluble nitrophospho‐molybdate complex is finally stained with the basic dye, Methyl Green Soluon. The reagents in this kit hydrolyze the phosphoester linkage of phosphoserine and phosphothreonine. Phosphotyrosine is not hydrolyzed and cannot be detected with this kit. The limit of detecon of this stain depends on several factors, including the molar amount of phosphate loaded onto the gel, the accessibility of these groups within the electrophoresed sample to hydrolysis during the staining procedure and molecules amount of phosphate in phosphoprotein. Therefore, lower limits of detecon must be determined empirically for each phosphoprotein.The kit is sufficient for 10 minigel stains.