Newly Determined Carboxy Terminal Sequences in Tropoelastin: Immunologic Identification in Insoluble Elastin

The carboxy terminal sequence of sheep, bovine and human tropoelastin (GFPGGACLGKA/SCGRKRK) has been inferred in earlier studies from sequencing of cloned complementary and genomic DNA. However, this putative carboxy terminal sequence was not found previously in peptides recovered from tryptic digests of tropoelastin. In order to determine whether the amino acid sequence described above is found in insoluble elastin, antibodies were raised against the chemically synthesized peptides with the appropriate sequences and the antibodies were shown to react with peptides derived from human, bovine, porcine, dog and hamster insoluble elastins. These results strongly suggest that the sequence (GFPGGACLGKA/SCGRKRK) at the carboxy terminus of tropoelastin is found in the elastins of many species.