Classification and Functional Characterization of the PP1-binding Proteins
Phosphorylation and dephosphorylation of proteins carried out by kinases and phosphatases is an important mechanism that controls the function and regulation of many pathways in the cell. Protein phosphatase 1 (PP1) is a member of the Serine/Threonine phosphatase family that is implicated in the regulation of many processes in the cell. It is responsible for the dephosphorylation of key proteins that are a part of muscle contraction, apoptosis, memory, neuronal signaling, tumor suppression, glycogen metabolism, etc. In human cells, the function and specificity of PP1 is regulated by a diverse group of regulators. The regulators interact with PP1 using short motifs. The most common motif of interaction that has been shown to be utilized by many regulators is the RVXF motif. In addition to this motif there are a few others like SILK, MyPhoNE and ϕϕ motif that have been described in some regulators. The number of regulators that interact with PP1 is increasing and there is a need to study these interactions broadly. The question we are trying to answer is – Are there any additional motifs that are utilized by regulators to bind to PP1 than RVXF? Can we classify and characterize the motifs in order to map them in all the regulator sequences ? We make use of in silico techniques like programming and statistical motif searching tools to answer these questions.