MP1 (MEK partner 1) functions as a scaffolding protein in the mitogen activated protein (MAP) kinase signaling pathway. Growth factor induced MAP kinase activation is selectively mediated by the extracellular signal-regulated kinase (ERK) cascade. MAPBPIP (mitogen-activated protein-binding protein-interacting protein), also known as p14 and late endosomal/lysosomal MP1-interacting protein, functions as an adaptor protein augmenting the regulation of the MAP kinase cascade. Partner proteins MAPBPIP and MP1 are structurally almost identical each with a five-stranded â^-sheet flanked between a two-helix and one-helix layer. MAPBPIP compels the recruitment of MP1 to late endosomes where they form a very stable heterodimeric complex required for ERK activation on endosomes. Knockdown of the individual proteins in the MP1/MAPBPIP complex resulted in decreased expression of the partner proteins which implies greater stability of the heterodimeric complex than either MP1 or MAPBPIP individually. Early research suggests the MP1-MAPBPIP-MEK-1 signaling complex may be critical in the regulation of tissue homeostasis.
Synonyms: ENDAP, Endosomal adaptor protein p14, HSPC003, LAMTOR2, Late endosomal/lysosomal adaptor and MAPK and MTOR activator 2, Late endosomal/lysosomal Mp1 interacting protein, Late endosomal/lysosomal Mp1-interacting protein, LTOR2_HUMAN, MAPBPIP, MAPKSP1 adaptor protein, MAPKSP1AP, Mitogen activated protein binding protein interacting protein, Mitogen-activated protein-binding protein-interacting protein, p14, Ragulator complex protein LAMTOR2, Ragulator2, Roadblock domain containing 3, Roadblock domain containing protein 3, Roadblock domain-containing protein 3, ROBLD 3, RP11 336K24.9.