Figure 4.

Anti-calretinin antiserum recognizes calbindin-D28k in calretinin-deficient mice and recombinant calbindin-D28k when Ca²⁺-saturated. (A) Western blot analysis. Proteins isolated from brain and cerebellum of Cr^+/+ and Cr^−/− mice and transferred onto the same filter were probed either with anticalretinin or anti-calbindin-D28k antibodies. (B) Immunoprecipitation of a protein at the expected size of 30,000 Da from Cr^+/+ cerebellum and of a 27,000-Da protein from Cr^−/− cerebellum. NRS, normal rabbit serum. (C) Western blot analysis using increased amounts of proteins isolated from cerebellum probed with anti-calbindin-D28k antibody shows no difference in calbindin-D28k-immunoreactivity. (D) Serial dilutions of purified recombinant calbindin-D28k preincubated in presence or absence of 3 mM calcium were immunoblotted by using the anticalretinin antiserum. Only calbindin-D28k saturated in Ca²⁺ could be detected.