A gene designated tfs1 has been isolated from Schizosaccharomyces pombe based on its similarity to genes encoding transcription elongation factor TFIIS. The nucleotide sequence of the tfs1 gene predicts a polypeptide with similarity to mammalian. Drosophila and Saccharomyces cerevisiae TFIIS. A haploid Sz. pombe strain with tfs1 deleted from the genome is viable. Thus, tfs1 is not essential for viability. However, deletion of tfs1 results in slow growth and increased sensitivity to the drug 6-azauracil, a phenotype similar to that of a S. cerevisiae strain deleted for the gene encoding TFIIS. The DNA sequence of tfs1 has been deposited in GenBank under Accession Number U20526.