Protein phosphatase-1 (PP1) is a prominent member of the Phosphoprotein Phosphatases family, and it catalyzes the majority of Ser/Thr dephosphorylation reactions. This broad range of functions is tightly regulated by its ability to form hundreds of holoenzymes by swapping a variety of regulatory subunits known as PP1-interacting proteins (PIPs). PIPs are seemingly unrelated in sequence and structure, but share a number of PP1-binding motifs (PP1-BMs). This common trait allows PIPs to combine multiple motifs and bind distinctive sites on PP1 surface to assemble unique holoenzymes. Although the majority of known PP1-BMs are unstructured short linear motifs (SLIMs), some are highly structured. Previous PP1 interactome mapping derives from high-throughput techniques combined with bioinformatics approaches that exploit SLIM PP1-BMs in proteome-wide screens based on sequence homology. Even though the number of known structured PP1-BMs is scarce when compared with the number of established SLIMs, it seems reasonable to expect that structural homology of proteins subunits (domains) could also be applied to expand the PP1 interactome. The present study explores structure-based PrePPI predictions to identify new PP1 interactors
