D PCDH7 and PCDH1 enriched on endoplasmic reticulum fraction. Whole‐cell lysate, cytoplasmic, endoplasmic, and mitochondrial fractions were blotted against an endoplasmic reticulum protein, KDEL, a cytoplasmic protein, actin, a mitochondrial protein Cox‐2 and PCDH7, PCDH1. 