THE FISSION YEAST PRP4+ GENE INVOLVED IN PREMESSENGER RNA SPLICING CODES FOR A PREDICTED SERINE THREONINE KINASE AND IS ESSENTIAL FOR GROWTH/

Only four prp (pre-mRNA processing) genes of the fission yeast Schizos accharomyces pombe have been reported. We exploited yeast genetics and identified and isolated the prp4 gene. Sequence analysis revealed tha t the splicing factor encoded by this gene contains the signature sequ ences that define the serine/threonine protein kinase family. This is the first kinase gene identified whose product is involved in pre-mRNA splicing. The prp4 gene contains one intron in the kinase domain. Gen e replacement studies provided evidence that this gene is essential fo r growth and is located on chromosome III.