Sequence of a cDNA for mouse thymidylate synthase reveals striking similarity with the prokaryotic enzyme

• Published in: Molecular biology and evolution Vol. 3; no. 4; pp. 313 - 321
• Main Authors: PERRYMAN, S. M, ROSSANA, C, DENG, T, VANIN, E. F, JOHNSON, L. F
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.07.1986
• Subjects: Amino Acid Sequence; Bacteriophages - genetics; Base Sequence; Biological and medical sciences; Biological evolution; DNA - genetics; DNA, Bacterial - genetics; Fundamental and applied biological sciences. Psychology; Genes, Bacterial; Genes, Viral; Genetics of eukaryotes. Biological and molecular evolution; Molecular Sequence Data; RNA, Messenger - genetics; Thymidylate Synthase - genetics; Nucleotide sequence; Enzyme; Biological evolution; Rodentia; Homology; Thymidylate synthase; Molecular evolution; Vertebrata; Mammalia; Procaryote; Complementary DNA; Gene; Mouse
• ISSN: 0737-4038; 1537-1719; 1537-1719
• DOI: 10.1093/oxfordjournals.molbev.a040400

We report the nucleotide sequence of a cloned cDNA, pMTS-3, that contains a 1-kb insert corresponding to mouse thymidylate synthase (E.C. 2.1.1.45). The open reading frame of 921 nucleotides from the first AUG to the termination codon specifies a protein with a molecular mass of 34,962 daltons. The predicted amino acid sequence is 90% identical with that of the human enzyme. The mouse sequence also has an extremely high degree of similarity (as much as 55% identity) with prokaryotic thymidylate synthase sequences, indicating that thymidylate synthase is among the most highly conserved proteins studied to date. The similarity is especially pronounced (as much as 80% identity) in the 44-amino-acid region encompassing the binding site for deoxyuridylic acid. The cDNA sequence also suggests that mouse thymidylate synthase mRNA lacks a 3' untranslated region, since the termination codon, UAA, is followed immediately by a poly(A) segment.