t-Loops in yeast mitochondria.

Mitochondria of several yeast species contain a linear DNA genome possessing specific terminal DNA structures dubbed mitochondrial telomeres. Several tandemly repeated units and a 5' single-stranded extension characterize mitochondrial telomeres in Candida parapsilosis, Pichia philodendra and Candida salmanticensis. Resemblance of this type of mitochondrial telomeres to typical nuclear telomeres suggests that they might form t-loop structures. Therefore we adopted a protocol for stabilization of potential t-loops in the mtDNA of C. parapsilosis and observed several loops at the ends of the mtDNA. A potential role of t-loops in protection of the ends of mtDNA and/or in mitochondrial telomere dynamics is discussed.