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.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3471242 | PMC |
http://dx.doi.org/10.1083/jcb.201205106 | DOI Listing |
Pharmaceuticals (Basel)
October 2024
Univ Rouen Normandie, INSA Rouen Normandie, CNRS, COBRA UMR 6014, F-76000 Rouen, France.
In connection with previous work on V-shaped polycyclic thiazolo[5,4-]quinazolin-9-one and [5,4-]quinazoline derivatives that can modulate the activity of various kinases, the synthesis of straight thiazole-fused [4,5-] or [5,4-]quinazolin-8-ones and quinazoline derivatives hitherto undescribed was envisioned. An innovative protocol allowed to obtain the target structures. The synthesis of inverted thiazolo[4,5-] and [5,4-]quinazolin-8-one derivatives was also explored with the aim of comparing biological results.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic.
Protein kinases are key regulators of numerous biological processes and aberrant kinase activity can cause various diseases, particularly cancer. Herein, we report the identification of new series of highly selective kinase inhibitors based on the thieno[3,2-b]pyridine scaffold. The weak interaction of the thieno[3,2-b]pyridine core with the kinase hinge region allows for profoundly different binding modes all of which maintain high kinome-wide selectivity, as illustrated by the isomers MU1464 and MU1668.
View Article and Find Full Text PDFRSC Med Chem
October 2024
Universite Claude Bernard Lyon 1, CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), COSSBA Team, Faculté de Pharmacie, ISPB 8, avenue Rockefeller F-69373 Lyon Cedex 08 France
A series of sulfur-containing tetracycles was designed and evaluated for their ability to inhibit protein kinase DYRK1A, a target known to have several potential therapeutic applications including cancers, Down syndrome or Alzheimer's disease. Our medicinal chemistry strategy relied on the design of new compounds using ring contraction/isosteric replacement and constrained analogy of known DYRK1A inhibitors, thus resulting in their DYRK1A inhibitory activity enhancement. Whereas a good inhibitory effect of targeted DYRK1A protein was observed for 5-hydroxy compounds 4i-k (IC = 35-116 nM) and the 5-methoxy derivative 4e (IC = 52 nM), a fairly good selectivity towards its known DYRK1B off-target was observed for 4k.
View Article and Find Full Text PDFFront Cell Dev Biol
September 2024
Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
Biology (Basel)
September 2024
Department of Urology, Juntendo University Urayasu Hospital, Chiba 279-0021, Japan.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!