A retention mechanism for distribution of mitochondria during cell division in budding yeast.
Mitochondria are indispensable for normal eukaryotic cell function. As they cannot be synthesized de novo and are self-replicating, mitochondria must be transferred from mother to daughter cells. Studies in the budding yeast Saccharomyces cerevisiae indicate that mitochondria enter the bud immediately after bud emergence, interact with the actin cytoskeleton for linear, polarized movement of mitochondria from mother to bud, but are equally distributed among mother and daughter cells [1] [2] [3]. It is not clear how the mother cell maintains its own supply of mitochondria. Here, we found that mother cells retain mitochondria by immobilization of some mitochondria in the 'retention zone', the base of the mother cell distal to the bud. Retention requires the actin cytoskeleton as mitochondria colocalized with actin cables in the retention zone, and mutations that perturb actin dynamics or actin-mitochondrial interactions produced retention defects. Our results support the model that equal distribution of mitochondria during cell division is a consequence of two actin-dependent processes: movement of some mitochondria into the daughter bud and immobilization of others in the mother cell.
Yang
H C
HC
Department of Anatomy and Cell Biology Columbia University College of Physicians and Surgeons New York, New York, 10032, USA.
Palazzo
A
A
Swayne
T C
TC
Pon
L A
LA
D000199:Actins / Q000378:metabolism / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology*; D016764:Cell Polarity / Q000502:physiology; D005656:Fungal Proteins / Q000502:physiology; D049452:Green Fluorescent Proteins; D006918:Hydroxyurea / Q000494:pharmacology; D007700:Kinetics; D008164:Luminescent Proteins / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000187:drug effects / Q000648:ultrastructure
D000199:Actins; D005656:Fungal Proteins; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins; D006918:Hydroxyurea