CryoEM and computational modeling structural insights into the pH regulator NBCn1.

ABSTRACT: Breast cancer cells survive despite being exposed to a toxic acidic extracellular environment, by utilizing the NBCn1 transporter. The molecular basis for this phenomenon is unknown, given the lack of an NBCn1 atomic structural model. We therefore determined the 3.3 Å cryoEM structure of the human NBCn1 outward facing (OF) conformational state with densities corresponding to the transported ions in the ion coordination site. We further generated NBCn1 inward facing (IF) and intermediate (occluded) structures and characterized the transport cycle and the ion dynamics in the IF and OF states. The results showed that NBCn1 utilizes an elevator-type transport mechanism with a small vertical shift of the ion coordination site between OF and IF conformational states and that the transported ions

SUBMITTER: Wang W 

PROVIDER: S-EPMC12606367 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature