Figure 1

The ura2 _15,30,72 allele and its corresponding multifunctional protein Ura2p. ns15 and ns30 correspond to the positions of the non-sense mutations and fs72 to the position of the frameshift mutation. GATase stands for Glutamine AmidoTransferase, CPSase for carbamylphosphate synthetase, DHOase-like for dihydroorotase-like and ATCase for aspartyltranscarbamylase.