Figure 8. Representative sucrose density gradient ultracentrifugation experiment of the distribution of Npt2a (top) and NHERF-1 (bottom).

Triton X-100–treated plasma membranes were harvested from NHERF-1^–/– cultured proximal tubule cells infected with wild-type GFP-NHERF-1 or from NHERF-1^–/– cells infected with NHERF-1 containing either the S77A or the S77D mutation. All cells were studied in the absence or presence of PTH. Each row was run as a separate gel under the same experimental conditions. The white line demarcates noncontiguous lanes within the same gel.