Small-molecule transporters of the lysosomal membrane export lysosomal catabolites for reuse in cell metabolism.
These transporters often show substrate promiscuity and, conversely, a given metabolite is often exported through distinct transport routes and sometimes in different states (e.g., single amino acids versus dipeptides).
Some lysosomal transporters import metabolites into the lumen. The combination of importers and exporters can create small-molecule shuttles across the lysosomal membrane, which regulate the lumen state.
Some lysosomal transporters participate in intracellular signaling cascades. sciencenewshighlights ScienceMission https://sciencemission.com/lysosomal-small-molecule-transporters
Lysosomes degrade damaged or unwanted cell/tissue components and recycle their building blocks through small-molecule transporters of the lysosomal membrane. They also act as signaling hubs that sense and signal internal cues, such as amino acids, to coordinate cell responses. Recently, the activity of several lysosomal metabolite transporters has been elucidated, bringing new insights into lysosomal functions. Cell biological and structural studies of lysosomal transporters have also highlighted their roles in recruiting signaling complexes to lysosomes and delineated how their substrates gate such hybrid transporter/receptor, or ‘transceptor’, function.
