<p>Protein phosphorylation, which plays a key role in most cellular activities, is a reversible process mediated by protein kinases and phosphoprotein phosphatases. Protein kinases catalyse the transfer of the gamma phosphate from nucleotide triphosphates (often ATP) to one or more amino acid residues in a protein substrate side chain, resulting in a conformational change affecting protein function. Phosphoprotein phosphatases catalyse the reverse process. Protein kinases fall into three broad classes, characterised with respect to substrate specificity [<cite idref="PUB00005115"/>]:</p><p> <ul> <li>Serine/threonine-protein kinases</li><li>Tyrosine-protein kinases</li><li>Dual specific protein kinases (e.g. MEK - phosphorylates both Thr and Tyr on target proteins)</li> </ul> </p><p>Protein kinase function has been evolutionarily conserved from <taxon tax_id="562">Escherichia coli</taxon> to human [<cite idref="PUB00020114"/>]. Protein kinases play a role in a multitude of cellular processes, including division, proliferation, apoptosis, and differentiation [<cite idref="PUB00015362"/>]. Phosphorylation usually results in a functional change of the target protein by changing enzyme activity, cellular location, or association with other proteins. The catalytic subunits of protein kinases are highly conserved, and several structures have been solved [<cite idref="PUB00034898"/>], leading to large screens to develop kinase-specific inhibitors for the treatments of a number of diseases [<cite idref="PUB00034899"/>].</p><p>Protein kinases are a group of enzymes that possess a catalytic subunit, which transfers the gamma phosphate from nucleotide triphosphates (often ATP) to one or more amino acid residues (such as serine, threonine, or tyrosine) in a substrate protein's side chain, resulting in a conformational change affecting protein function. Protein kinase function has been evolutionarily conserved from <taxon tax_id="562">Escherichia coli</taxon> to <taxon tax_id="9606">Homo sapiens</taxon> (Human), where they play a role in a multitude of cellular processes, including division, proliferation, apoptosis, and differentiation [<cite idref="PUB00015362"/>].</p> <p>The catalytic subunits of protein kinases are highly conserved, and several structures have been solved [<cite idref="PUB00034898"/>], leading to large screens to develop kinase-specific inhibitors for the treatments of a number of diseases [<cite idref="PUB00034899"/>].</p> <p>Anti-Mullerian hormone (AMH), also called Mullerian inhibiting substance, is a member of the transforming growth factor beta (TGF-beta) family that represses the development and function of reproductive organs [<cite idref="PUB00034960"/>]. Anti-Mullerian hormone is thought to exert its effects through two membrane-bound serine/threonine kinase receptors, type 2 and type 1. Upon ligand binding, these drive receptor-specific cytoplasmic substrates, the Smad molecules, into the nucleus where they act as transcription factors. A type 2 receptor specific for AMH was cloned through its homology with receptors of TGF-beta family members. Components of the AMH signalling pathway have been identified in gonads and gonadal cell lines. The AMH type II receptor is highly specific. In contrast, the identity of the AMH type I receptor is not clear.</p> Anti-muellerian hormone receptor, type II