Haspin inhibitors reveal centromeric functions of Aurora B in chromosome segregation.
Haspin phosphorylates histone H3 at threonine-3 (H3T3ph), providing a docking site for the Aurora B complex at centromeres. Aurora B functions to correct improper kinetochore-microtubule attachments and alert the spindle checkpoint to the presence of misaligned chromosomes. We show that Haspin inhibitors decreased H3T3ph, resulting in loss of centromeric Aurora B and reduced phosphorylation of centromere and kinetochore Aurora B substrates. Consequently, metaphase chromosome alignment and spindle checkpoint signaling were compromised. These effects were phenocopied by microinjection of anti-H3T3ph antibodies. Retargeting Aurora B to centromeres partially restored checkpoint signaling and Aurora B-dependent phosphorylation at centromeres and kinetochores, bypassing the need for Haspin activity. Haspin inhibitors did not obviously affect phosphorylation of histone H3 at serine-10 (H3S10ph) by Aurora B on chromosome arms but, in Aurora B reactivation assays, recovery of H3S10ph was delayed. Haspin inhibitors did not block Aurora B localization to the spindle midzone in anaphase or Aurora B function in cytokinesis. Thus, Haspin inhibitors reveal centromeric roles of Aurora B in chromosome movement and spindle checkpoint signaling.
Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Fangwei
F
Wang
Natalia P
NP
Ulyanova
John R
JR
Daum
Debasis
D
Patnaik
Anna V
AV
Kateneva
Gary J
GJ
Gorbsky
Jonathan M G
JM
Higgins
D000906:Antibodies / Q000276:immunology; D064107:Aurora Kinase B; D064127:Aurora Kinases; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D002503:Centromere / Q000502:physiology*; D020090:Chromosome Segregation; D006367:HeLa Cells; D006657:Histones / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors*; D059566:M Phase Cell Cycle Checkpoints / Q000187:drug effects; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D015398:Signal Transduction; D014372:Tubercidin / Q000031:analogs & derivatives / Q000494:pharmacology
D000906:Antibodies; D018797:Cell Cycle Proteins; D006657:Histones; D047908:Intracellular Signaling Peptides and Proteins; C034214:5-iodotubercidin; C576921:AURKB protein, human; D064107:Aurora Kinase B; D064127:Aurora Kinases; C530656:HASPIN protein, human; D017346:Protein Serine-Threonine Kinases; D014372:Tubercidin