EXPRESSION OF TAU-EXON-8 IN DIFFERENT SPECIES

A synthetic peptide corresponding to a region encoded by tau gene exon 8 was used to raise an antibody. The antibody, E8, was used to probe normal tau from different species and abnormal tau proteins from subje cts with Alzheimer's disease. Immunoblotting and enzyme-linked immunos orbent assays demonstrated that only bovine tau reacted with the E8 an tibody. The E8 immunoreactive tau isoform was estimated to represent l ess than 2% of the bovine tau. Our results indicate that bovine tau is unique in containing isoforms positive with E8, and that PHF formatio n does not require the presence of PHF-tau with exon 8.