Total synthesis of a tyrosine suppressor transfer RNA gene. XIII. Synthesis of deoxyribopolynucleotide segments corresponding to the nucleotide sequence -1 to -29 in the promoter region.

Chemical syntheses of two tridecanucleotides, d(G-C-A-T-C-A-T-A-T-C-A-A-A) and d(G-C-G-T-C-A-T-T-T-G-A-T-A), and three undecanucleotides, d(G-G-A-A-G-C-G-G-G-G-C), d(T-G-A-T-G-C-G-C-C-C-C), and d(T-G-A-C-G-C-G-C-C-G-C), are described. These deoxyribo-oligonucleotide segments together represent the DNA duplex corresponding to the previously determined nucleotide sequence -1 to -29 of the promoter region of the tyrosine tRNA gene (Sekiya, T., van Ormondt, H., and Khorana, H.G. (1975) J. Biol. Chem. 250, 1087-1098). Chemical syntheses used the principles of stepwise addition of protected mono- and oligonucleotides to the 3'-hydroxyl end of growing oligonucleotide chains. The desired condensation products were isolated by solvent extraction methods in the case of di- and trincleotides and by anion exchange chromatography in the case of longer chains. All the five synthetic oligonucleotides were characterized by chromatographic and radioactive fingerprinting methods after labeling at the 5'-ends with a [32P]phosphate group.