Chromosomes can congress to the metaphase plate before biorientation.
The stable propagation of genetic material during cell division depends on the congression of chromosomes to the spindle equator before the cell initiates anaphase. It is generally assumed that congression requires that chromosomes are connected to the opposite poles of the bipolar spindle ("bioriented"). In mammalian cells, we found that chromosomes can congress before becoming bioriented. By combining the use of reversible chemical inhibitors, live-cell light microscopy, and correlative electron microscopy, we found that monooriented chromosomes could glide toward the spindle equator alongside kinetochore fibers attached to other already bioriented chromosomes. This congression mechanism depended on the kinetochore-associated, plus end-directed microtubule motor CENP-E (kinesin-7).
Kapoor
Tarun M
TM
Laboratory of Chemistry and Cell Biology, Rockefeller University, New York, NY 10021, USA.
Lampson
Michael A
MA
Hergert
Polla
P
Cameron
Lisa
L
Cimini
Daniela
D
Salmon
E D
ED
McEwen
Bruce F
BF
Khodjakov
Alexey
A
D000818:Animals; D064127:Aurora Kinases; D002460:Cell Line; D002868:Chromosomal Proteins, Non-Histone / Q000502:physiology; D033481:Chromosomes, Mammalian / Q000502:physiology* / Q000648:ultrastructure; D006367:HeLa Cells; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D016547:Kinesins / Q000037:antagonists & inhibitors; D018386:Kinetochores / Q000502:physiology* / Q000648:ultrastructure; D008677:Metaphase; D018613:Microscopy, Confocal; D008854:Microscopy, Electron; D008857:Microscopy, Interference; D018715:Microscopy, Video; D008870:Microtubules / Q000502:physiology* / Q000648:ultrastructure; D008938:Mitosis; D020409:Molecular Motor Proteins / Q000502:physiology; D009068:Movement; D048328:Potoroidae; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D011743:Pyrimidines / Q000494:pharmacology; D034622:RNA Interference; D034741:RNA, Small Interfering; D008941:Spindle Apparatus / Q000502:physiology* / Q000648:ultrastructure; D013449:Sulfonamides / Q000494:pharmacology; D013871:Thiones / Q000494:pharmacology
D002868:Chromosomal Proteins, Non-Histone; D007211:Indoles; D020409:Molecular Motor Proteins; D011743:Pyrimidines; D034741:RNA, Small Interfering; D013449:Sulfonamides; D013871:Thiones; C068688:centromere protein E; C400223:monastrol; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases; D016547:Kinesins; C474723:hesperadin