Synergistic roles of aquaporin 5 and intra- and extracellular carbonic anhydrases in promoting CO₂ diffusion across the Xenopus oocyte plasma membrane.

ABSTRACT: CO₂ diffusion across plasma membranes depends on both membrane CO₂ permeability ( PM,CO2${P_{{\mathrm{M,C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ) and the transmembrane CO₂ concentration gradient (Δ[CO₂]) - Fick's law. Human aquaporin-5 (hAQP5) enhances CO₂ diffusion by increasing PM,CO2${P_{{\mathrm{M,C}}{{\mathrm{O}}_{\mathrm{2}}}}}$ , whereas carbonic anhydrases (CAs) do so by enhancing CO₂ consumption/production and thus Δ[CO₂]. Here we systematically assess functional interactions among a gas channel and intra-/extracellular CAs. On Day 1 we inject Xenopus oocytes with cRNA encoding hAQP5 (control: H₂O). On Day 4 we inject hCA II protein in 'Tris' buffer (control: 'Tris'). We assess CO₂ fluxes

SUBMITTER: Wang DK 

PROVIDER: S-EPMC12871926 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature