FIG 5 .

Model of mtDNA inheritance in Cryptococcus. Under mating-inducing conditions, the a cell activates Mat2 and produces high levels of the MFa pheromone (8). In response to MFa, the α cell activates Mat2 and produces a conjugation tube. The earlier induction of Mat2 at a higher level in the a cell marks its mitochondria for preservation. Immediately after cell fusion, the Sxi1α/Sxi2a complex forms, and it helps degrade the unprotected α mitochondria in the newly formed zygote. Thus, the a mitochondria dominate in the mature zygote and cells subsequently generated from that zygote (e.g., hyphae and spores).