Abnormal accumulation of HP1α in CDA-1 erythroblasts is erythroid specific. (A) Accumulation of HP1α in CDA-1 intermediate erythroblasts by immunofluorescent microscopy. (B) Staining with Golgi-apparatus marker (giantin) confirms localization of HP1α in the Golgi apparatus. (C) Lack of abnormal localization in EBV-derived lymphoblasts from CDA-1 patients and CDA-2 intermediate erythroblasts. (D) Quantification of HP1α in primary erythroblasts and matched EBV-transformed lymphoblasts of CDA-1 patients and controls. Western blotting of nuclear extracts of primary erythroblasts (NucE; left) and of whole-cell extracts of EBV-transformed lymphoblasts (WCE; right).