Mucolipin transient receptor potential cation channel 1 (TRPML1)

Mucolipin transient receptor potential cation channel 1 (TRPML1) is a **lysosomal ion channel** encoded by the MCOLN1 gene, belonging to the transient receptor potential (TRP) channel superfamily, specifically the mucolipin subfamily. It is ubiquitously expressed in mammalian cells, where it functions as a calcium- and iron-permeable channel, regulating the release of ions from endosomal and lysosomal compartments into the cytoplasm[1][2][3][4][6][7]. TRPML1 is crucial for vesicular trafficking, autophagy, lysosome pH and membrane potential, and cellular responses to oxidative stress. Loss-of-function mutations cause mucolipidosis type IV, a severe neurodegenerative lysosomal storage disorder characterized by psychomotor delay, vision loss, and defective iron metabolism. As a result, TRPML1 is considered a promising therapeutic target for treating lysosome-associated neurodegenerative diseases[1][3][4][6]. **Key characteristics include**: - Structure: Six transmembrane domains, with a cation channel domain and pore[2][1]. - Ligand modulation: Physiologically activated by phosphatidylinositol-3,5-bisphosphate (PI(3,5)P₂), inhibited by PI(4,5)P₂ and sphingomyelins; synthetic agonists such as ML-SA1 and MK6-83 are described[4][7]. - Pathophysiological relevance: Dysfunction leads to accumulation of storage material, defective autophagy, oxidative stress, and impaired cellular signaling, particularly in neurological tissues[4][3]. - Research tools and druggability: Multiple small molecules modulate channel function, supporting its role as a drug discovery target[2][7].

Other names

Mucolipin-1ML1MCOLN1Transient receptor potential cation channel, mucolipin subfamily, member 1

Activation (agonism) opens the Ca²⁺-permeable channel, promoting lysosomal ion release and restoring functions in disease models[7][4][2]. Inhibition blocks cation flow, contributing to pathology or experimental modulation[4][7].