Figure 3.

Antibody specificity to actinin-1 and -4. (A) A polypeptide of actinin-4 (amino acids 410–664) and a corresponding site of actinin-1 (amino acids 418–672) were expressed as GST fusion proteins in E. coli. Immunoblot analysis revealed that NCC- Lu-632 mAb reacts only with the actinin-4 GST fusion protein (ACTN4 GST), and not with the actinin-1 GST fusion protein (ACTN1 GST) or GST alone (GST). Molecular masses (in kD) are shown on the left. (B) Coomassie blue staining of the blot corresponding to that in A, demonstrating proper protein loading in each lane. (C) In vitro translation products of actinin-1 and -4. SDS-PAGE and autoradiography reveal ³⁵S-labeled actinin-1 and -4 proteins. Molecular masses (in kD) are shown on the left. (D) In vitro translation products of actinin-1 (ACTN 1) and actinin-4 (ACTN 4) were immunoprecipitated by anti–chicken actinin mAb BM-75.2 or normal mouse IgM. Actinin-1 but not actinin-4 was precipitated with BM-75.2. Molecular masses (in kD) are shown on the left.