Mps1 and Ipl1/Aurora B act sequentially to correctly orient chromosomes on the meiotic spindle of budding yeast.
The conserved kinases Mps1 and Ipl1/Aurora B are critical for enabling chromosomes to attach to microtubules so that partner chromosomes will be segregated correctly from each other, but the precise roles of these kinases have been unclear. We imaged live yeast cells to elucidate the stages of chromosome-microtubule interactions and their regulation by Ipl1 and Mps1 through meiosis I. Ipl1 was found to release kinetochore-microtubule (kMT) associations after meiotic entry, liberating chromosomes to begin homologous pairing. Surprisingly, most chromosome pairs began their spindle interactions with incorrect kMT attachments. Ipl1 released these improper connections, whereas Mps1 triggered the formation of new force-generating microtubule attachments. This microtubule release and reattachment cycle could prevent catastrophic chromosome segregation errors in meiosis.
Department of Cell Cycle and Cancer Biology, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA.
Régis E
RE
Meyer
Seoyoung
S
Kim
David
D
Obeso
Paul D
PD
Straight
Mark
M
Winey
Dean S
DS
Dawson
D064127:Aurora Kinases; D020090:Chromosome Segregation / Q000235:genetics / Q000502:physiology*; D015825:Chromosomes, Fungal / Q000235:genetics*; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000502:physiology*; D018386:Kinetochores / Q000201:enzymology; D008540:Meiosis / Q000235:genetics / Q000502:physiology*; D008870:Microtubules / Q000201:enzymology; D009154:Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000502:physiology*
D047908:Intracellular Signaling Peptides and Proteins; D029701:Saccharomyces cerevisiae Proteins; D064127:Aurora Kinases; C576961:IPL1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; C093416:MPS1 protein, S cerevisiae