Nucleic Acids Research, 1985, Vol. 13, No. 24 8739-8747
© 1985
Articles |
Dimeric tRNA gene arrangement in Schizosaccharomyces pombe allows increased expression of the downstream gene
Department of Molecular Biophysics and Biochemistry, Yale University New Haven, CT 06511, USA
*To whom correspondence should be addressed
Received October 11, 1985. Accepted November 13, 1985.
Three Schizosaccharomyces pombe dimeric tRNA genes, consisting of a tRNASer gene encoding a minor species with an intervening sequence followed by a tRNAMeti gene, have been described [Mao et al. (1980) Cell 21, 509–516: Hot-tinger et al. (1982) Mol. Gen. Genet. 188, 219–224; Willis et al. (1984) EMBO J. 3, l573–1580]. We have examined the reason for the dimeric structure by comparing the transcriptional efficiencies and competitive abilities of the genes subcloned from the dimeric arrangement. Both of the subcloned genes are active in vivo in Saccharomyces cerevisiae, but only the tRNASer gene is efficiently transcribed in vitro. The tRNAMeti gene competes efficiently for transcription factors, while the tRNAMeti gene does so only weakly. Thus, it appears that the dimeric arrangement is required to support expression of the tRNAMeti gene. S. pombe genes encoding major species of tRNASer are transcribed considerably less efficiently than are the minor genes from the dimers, so coupling of the tRNAMeti gene to the minor species genes should lead to efficient production of tRNAMeti.