IRBIT activates NBCe1-B by releasing the auto-inhibition module from the transmembrane domain.

ABSTRACT:

Key points

The electrogenic Na⁺ /HCO₃^- cotransporter NBCe1-B is widely expressed in many tissues, including pancreas, submandibular gland, brain, heart, etc. NBCe1-B has very low activity under basal condition due to auto-inhibition, but can be fully activated by protein interaction with the IP3R-binding protein released with inositol 1,4,5-trisphosphate (IRBIT). The structural components of the auto-inhibition domain and the IRBIT-binding domain of NBCe1-B are finely characterized based on systematic mutations in the present study and data from previous studies. Reducing negative charges on the cytosol side of the transmembrane domain greatly decreases the magnitude of the auto-inhibition of NBCe1-B. We propose that the auto-inhibition domain funct

SUBMITTER: Su P 

PROVIDER: S-EPMC7898672 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature