Christella J. Nelson

1 Introduction Protein kinases regulate cellular processes by catalyzing phosphorylation of serine, threonine, or tyrosine residues, thereby altering protein activity, localization, and interactions. These enzymes activate the transfer of the gamma phosphate from ATP to specific serine, threonine, or tyrosine residues on their target proteins, thereby regulating fundamental processes such as signal transduction, cell cycle progression, metabolism, and immune responses [1].