A yeast ribosomal protein gene whose intron is in the 5' leader

The complete gene encoding yeast ribosomal protein 29, a component of the 60 S ribosomal subunit of Saccharomyces cerevisiae has been isolated and its nucleotide sequence determined. The coordinates of transcription initiation and termination of the rp29 gene have been mapped. Transcription appears to start at several sites, spanning nearly 30 nucleotides. The gene is transcribed into a precursor RNA molecule of 1110 to 1085 nucleotides from which an intron of 458 nucleotides is spliced out. The splice junction has been determined by comparing the nucleotide sequences of the rp29 gene with those of a homologous cDNA clone. Interestingly, the intron of the rp29 gene resides in the 5' untranslated region of the rp29 mRNA, the first instance where this has been observed in yeast. The single open reading frame in the rp29 gene encodes a very basic protein of 155 amino acid residues.