title: Interaction of Myosin Phosphatase Target Subunit (MYPT1) with Myosin Phosphatase-RhoA Interacting Protein (MRIP): A Role of Glutamic Acids in the Interaction.
abstract: Scaffold proteins bind to and functionally link protein members of signaling pathways. Interaction of the scaffold proteins, myosin phosphatase target subunit (MYPT1) and myosin phosphatase-RhoA interacting protein (MRIP), causes co-localization of myosin phosphatase and RhoA to actomyosin. To examine biophysical properties of interaction of MYPT1 with MRIP, we employed analytical ultracentrifugation and surface plasmon resonance. In regard to MRIP, its residues 724-837 are sufficient for the MYPT1/MRIP interaction. Moreover, MRIP binds to MYPT1 as either a monomer or a dimer. With respect to MYPT1, its leucine repeat region, LR (residues 991-1030) is sufficient to account for the MYPT1/MRIP interaction. Furthermore, point mutations that replace glutamic acids 998-1000 within LR reduced the binding affinity toward MRIP. This suggests that the glutamic acids of MYPT1 play an important role in the interaction.
authors.affiliation: Cardiovascular Biology Program and AUC Research Laboratory, Boston Biomedical Research Institute, 64 Grove St, Watertown, MA, 02472, United States of America.
authors.forename: Eunhee
authors.initials: E
authors.lastname: Lee
authors.affiliation: Cardiovascular Biology Program and AUC Research Laboratory, Boston Biomedical Research Institute, 64 Grove St, Watertown, MA, 02472, United States of America.
authors.forename: Walter F
authors.initials: WF
authors.lastname: Stafford
mesh_terms: D019281:Dimerization; D019204:GTP-Binding Proteins / Q000378:metabolism*; D020690:GTPase-Activating Proteins / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism*; D006801:Humans; D043263:Myosin-Light-Chain Phosphatase / Q000378:metabolism*; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D011994:Recombinant Proteins; D020349:Surface Plasmon Resonance; D014461:Ultracentrifugation
chemical_list: D020690:GTPase-Activating Proteins; D011994:Recombinant Proteins; D018698:Glutamic Acid; D043263:Myosin-Light-Chain Phosphatase; C490372:PPP1R12A protein, human; C472718:AGAP3 protein, human; D019204:GTP-Binding Proteins