Myosin-VIIa- and Rab-interacting protein (MYRIP)

Myosin-VIIa- and Rab-interacting protein (MYRIP) is a scaffold protein that directly binds to both the actin-based motor myosin VIIa and the small GTPase Rab27A, functioning as a Rab effector[2]. Its primary role is to bridge organelles—such as retinal melanosomes and secretory granules—to the actin cytoskeleton, facilitating their local transport and positioning within cells[2]. MYRIP contains an N-terminal FYVE/Rab-binding domain and a myosin VIIa–binding domain, which together enable it to form molecular complexes critical for dynamic vesicle trafficking, particularly in retinal pigment epithelium, inner ear hair cells, and neuroendocrine cells[2]. In pancreatic beta cells, MYRIP also acts as an atypical A-kinase anchoring protein (AKAP), positioning PKA for localized signaling and secretory granule phosphorylation in response to incretin and cAMP signaling; this function is crucial for regulated hormone (e.g., insulin) secretion[1]. Defects in the MYRIP/myosin VIIa/Rab27A complex can cause intracellular organelle mislocalization, contributing to retinal disorders and deafness in mammals[2]. MYRIP is broadly expressed and plays an important cell biology role, but it is not currently a therapeutic target.

Other names

Rab effector MyRIPSLAC2CSlaC2-cSlp homologue lacking C2 domains cexophilin-8SLAC2-CSynaptotagmin-like protein lacking C2 domains Csynaptotagmin-like protein homologue lacking C2 domains-cDKFZp586F1018