Fig. 3.

NHE3 is partially associated with lipid rafts, and the different NHERFs are differentially associated with the raft and non-raft fraction of BBM. A) NHE3 and the NHERF-PDZ adaptors in rafts and non-rafts of WT mice. Approx. 20% of total BBM NHE3 is found in the raft fractions, which are indicated as fractions 1–5. NHERF1 shows very little raft association, NHERF2 associates strongly with rafts, and NHERF3 is absent from the raft fractions. C), NHERF1 ablation resulted in increased NHE3 and NHERF2 in rafts. E), NHERF2 KO BBM show a decrease in NHE3 in intestinal rafts, demonstrating that NHE3 association with rafts is influenced by the presence of NHERF-2. G) NHERF3 KO BBM show an increase of NHERF1 and NHERF2 raft-association. The Western results correspond to 2–4 independent lipid raft isolations from BBM pooled from 4 mice each. B) Quantification of immune signals from A) NHERF WT BBM showed NHE3 (18%±0.16) and NHERF2 (41%±0.72) in rafts, while NHERF1 raft-association was not significant (2%±1.03) and NHERF3 not present at all, D) NHERF1 KO showed a significant increase in raft-associated proteins, NHE3 (34.2%±9.1) and NHERF2 (51%±4.4), F) NHERF2 KO showed a strong decrease in NHE3 (3.7%±2.7). H) NHERF3 KO BBM showed an increase of NHERF2 (78%±7.6) and NHERF1 (11%±2.56), but not of NHE3, in the raft fraction. n=2–4, p>0.05.