Figure 1.

Expression of Necl proteins by Schwann cells and DRG neurons. (A) Schematic organization of the Necl protein family. The extracellular segment contains three Ig domains of the variable (V), constant-2 (C2), and intermediate (I) types; the cytoplasmic region contains FERM- and PDZ-binding motifs as indicated. (B) Staining of cultured Schwann cells (left column) and of DRG somas and neurites (middle and right columns) with antibodies to Necl-1–4 is shown. Schwann cell nuclei are stained in red. Antibodies to Necl-1, -3, and -4 recognize the ectodomain of these proteins; the Necl-2 antibody reacts with its C terminus. Necl-1 specifically stains neurons, whereas Necl-4 specifically stains Schwann cells. Necl-2 stains Schwann cell membranes, nuclei, and neurons. Necl-1–3 accumulate at sites of contact between the neuronal cell somas. Bars, 50 μm.