ATP synthase peripheral stalk subunit b, mitochondrial

ATP synthase peripheral stalk subunit b (ATP5PB) is a component of the mitochondrial F₀F₁-ATP synthase complex (Complex V), which catalyzes ATP synthesis from ADP using the proton gradient generated by the electron transport chain (UniProt: P24539). The protein functions as part of the peripheral stalk that acts as a stator, holding the catalytic core stationary relative to rotating central stalk elements during the rotary mechanism of ATP production.

ATP5PB localizes to the inner mitochondrial membrane within the F₀ domain and peripheral stalk structure (UniProt: P24539). No primary disease associations are documented in UniProt for this protein.

ATP5PB has been identified as relevant to Alzheimer's Disease through proteomic profiling of post-mortem AD brain tissue. However, the direction of dysregulation is ambiguous across subcellular fractions examined (Chaparral AD proteomics). The mean log₂ fold-change was 0.56, indicating modest overall elevation, though this masks heterogeneous changes across the four fractions (P2, P3, S2, S3) analyzed in the TMT-labeled discovery proteomics study.