Open AccessIn vitro synthesis of thymosin beta 4 encoded by rat spleen mRNA.
Author(s) -
Aleksandra Filipowicz,
B.L. Horecker
Publication year - 1983
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.80.7.1811
Subject(s) - reticulocyte , thymosin , microbiology and biotechnology , immunoprecipitation , messenger rna , beta (programming language) , biochemistry , peptide , lysis , protein biosynthesis , antiserum , polyacrylamide gel electrophoresis , in vitro , gel electrophoresis , biology , centrifugation , chemistry , amino acid , antigen , gene , enzyme , computer science , programming language , genetics
Thymosin beta 4, containing 43 amino acids and acetylated at the NH2 terminus, is synthesized in vitro in a rabbit reticulocyte lysate or in a yeast protein-synthesis system in the presence of mRNA from rat spleen. The product formed was identified as beta 4 by immunoprecipitation by a specific anti-beta 4 antiserum, comigration with authentic beta 4 in NaDodSO4/polyacrylamide gel electrophoresis and in HPLC, and identity of peptide fragments. The immunoprecipitable product generated in the wheat germ protein-synthesizing system emerged slightly ahead of beta 4 in HPLC and appeared to lack the NH2-terminal acetyl group. There was no evidence for formation of a larger polypeptide precursor of beta 4 in any of the three systems used. In sucrose density gradient centrifugation, the mRNA coding for beta 4 was recovered in the 7-8S mRNA fraction.