Solute carrier family 35 member B1 (SLC35B1)

Solute carrier family 35 member B1 (SLC35B1) is a membrane transporter protein localized to the endoplasmic reticulum (ER) that mediates the strict exchange of ATP and ADP across the ER membrane. SLC35B1 is essential for maintaining an intraluminal supply of ATP, fueling protein folding, quality control, and trafficking within the ER. The protein operates by a distinctive antiport mechanism, exchanging cytosolic ATP for luminal ADP, and its function is structurally distinct from canonical nucleotide sugar transporters; it does not bind nucleotide sugars but specifically mediates ATP/ADP exchange. SLC35B1 is evolutionarily conserved, and loss of its function leads to decreased ER ATP levels, impaired chaperone activity (e.g., reduced BiP function), and reduced cell growth, underscoring its fundamental role in cell biology. Dysregulation or dysfunction of SLC35B1 has been implicated or suggested in diseases involving ER stress, such as type 2 diabetes, cancer, and neurodegenerative disorders. Current research aims to identify small molecules that modulate SLC35B1 activity, which could offer new avenues for therapeutic intervention in ER stress-related diseases.

Other names

AXERUGTREL1Endoplasmic reticulum ATP/ADP translocaseATP/ADP exchanger ERUDP-galactose transporter-related protein 1ATP/ADP exchanger in the ER membrane