# DNA sequences and distinct mechanisms for ura4-595 and ura4-294 alleles of S. pombe

## TL;DR

This paper identifies DNA sequence differences in two non-functional versions of the ura4 gene in fission yeast and suggests how these mutations occurred.

## Contribution

The study provides new DNA sequence data and mutation mechanisms for two ura4 alleles in Schizosaccharomyces pombe.

## Key findings

- The ura4-595 allele has a four bp duplication in the ORF due to DNA polymerase template slipping.
- The ura4-294 allele has a nonsynonymous substitution likely caused by cytosine deamination.
- Both alleles are functionally null and used for positive and negative selection in research.

## Abstract

The
ura4
gene of the fission yeast
Schizosaccharomyces pombe
supports both positive and negative selection; consequently, this gene is widely employed as a powerful tool to study diverse biological processes. Here we report the DNA sequences of two functionally null alleles,
ura4-595
and
ura4-294
. The
ura4-595
allele has a four bp duplication of bp +63 to +66 (5’-CAAG-3’) within the ORF and the
ura4-294
allele has a nonsynonymous substitution (G to A) at bp +679. We infer that these alleles arose, respectively, by DNA polymerase template slipping and by nucleotide misincorporation (likely via cytosine deamination).