A gene coding for a ribosomal protein L41 in cycloheximide-resistant ribosomes has a promoter which is upregulated under the growth-inhibitory conditions in yeast, Candida maltosa.

We previously found by using yeast, Candida maltosa, that cycloheximide (CYH) sensitivity of ribosomes is dependent on the 56th amino acid residues of a ribosomal protein, L413 (proline in sensitive and glutamine in resistant ribosomes). We also revealed that in this yeast, which has both L41-P type and L41-Q type genes, the expression of the latter type genes is induced by the addition of CYH in the medium to make the cells inducibly resistant to CYH. In this paper, we analyzed the promoter region of L41-Q2a, one of the CYH-inducible L41-Q type genes and found two elements required for the induction of expression: one was a GCRE (Gcn4p-responsive element of Saccharomyces cerevisiae)-like element and the other was a GT-rich element. This promoter region was also required for its expression under some other growth inhibitory conditions. Furthermore, it was suggested that Q-type ribosomes synthesized under these conditions are more resistant to these inhibitory conditions.
(Copyright 1999 Academic Press.)