Figure 4.

IRBIT regulates NaDC-3–, but not OAT-mediated succinate transport. (A) Lack of CoIP of mOAT-1 and mOAT-3 with IRBIT. ¹⁴C succinate uptake, measured in either (B) Xenopus oocytes or (C) HEK293T cells expressing different combinations as indicated (mOAT-1, hSUCNR1, and IRBIT or treated with the PLC inhibitor U73122 or the OAT inhibitor probenecid). Either water-injected oocytes or pcDNA-transfected cells were used as control. (D) Summary and representative traces of mNaDC-3–dependent Na⁺ succinate cotransport in Xenopus oocytes expressing mNaDC-3, either alone (black) or with IRBIT (gray) (three oocyte batches). ***P<0.001.