Nephrin and NEPH1, the gene products of NPHS1 and NEPH1, are podocyte membrane
proteins of the Ig superfamily. Similar to the nephrin knockout, mice lacking NEPH1 show
severe proteinuria leading to perinatal death. To identify the ligand of NEPH1, the
extracellular domain of NEPH1 was fused to human IgG. This NEPH1-Ig fusion protein
labeled the glomerular capillary wall of mouse kidneys in a staining pattern identical to
NEPH1 and nephrin, prompting speculation that that NEPH1 might form homodimers and/or …