Primary structure and transcription patterns of RPL36, a ribosomal protein-encoding gene of the mycoparasitic fungus, Trichoderma hamatum

We report the isolation and expression profiles of a single-copy gene from the mycoparasitic fungus Trichoderma hamatum encoding a 60 S cytoplasmic ri bosomal protein. The gene, named RPL36, was cloned through its nutrient-med iated expression, using mRNA differential screening. Its predicted ORF, int errupted by two introns, encoded a 105-aa polypeptide. The deduced rpL36 pr otein showed high overall homologies with other L36-type ribosomal proteins isolated from yeast, rat and. human. Analysis of the promoter region of RP L36 revealed the presence of two ribosomal protein gene (RPG) boxes and a T -rich region known to be involved in the regulation of most ribosomal prote in genes. Expression of RPL36 was tightly regulated by carbon and nitrogen availability. The mRNA levels of this gene decreased upon exposure of the m ycelium to different stresses, whereas the addition of cycloheximide result ed, in a super-induction. Levels of RPL36 transcripts also increased during mycoparasitic interaction between T. hamatum and Botrytis cinerea.