FIG. 4.

Hyperrecombination phenotype of the ulp1-I615N mutant. (A) Papillation test of ulp1 homozygous diploids (MH1088) that were heteroallelic for ARG4 on synthetic medium lacking arginine. Clones with (right) or without (left) an ULP1⁺ copy were grown on arginine-containing medium before being replica plated onto medium lacking arginine (left) or onto medium lacking arginine and tryptophan to maintain the ULP1-containing plasmid (right). (B) The ulp1 homozygous diploids have a spontaneous hyperrecombination phenotype. Spontaneous recombination rates were measured at the ARG4 locus in the presence or absence of one or several ULP1⁺ copies.