Fig. 4. The abf2Δ and mgt1Δ mutant alleles inhibit the production of small circular oligomers of ρ^– HS40 mtDNA induced by activation of the general amino acid control pathway. One-dimensional gel electrophoresis of ∼20 μg samples of total DNA was used to resolve the different oligomeric forms of mtDNA. YNBD medium was supplemented with isoleucine, leucine and valine (ILV) as indicated in the figure. Supercoiled species are indicated as sc. As a loading control, 1 μg of total DNA was linearized by digestion with EcoRV and detected with an HS40 probe (lower panel).