Phosphorylation of histone H3 at Thr3 is part of a combinatorial pattern that marks and configures mitotic chromatin (Journal article)

Markaki, Y./ Christogianni, A./ Politou, A. S./ Georgatos, S. D.

We have previously shown that histone H3 is transiently phosphorylated at Thr3 during mitosis. Extending these studies, we now report that phosphorylated Thr3 is always in cis to trimethylated Lys4 and dimethylated Arg8, forming a new type of combinatorial modification, which we have termed PMM. PMM-marked chromatin emerges at multiple, peripheral sites of the prophase nucleus, then forms distinct clusters at the centric regions of metaphase chromosomes, and finally spreads (as it wanes) to the distal areas of segregating chromatids. The characteristic prophase pattern can be reproduced by expressing ectopically the kinase haspin at interphase, suggesting that the formation of the PMM signature does not require a pre-existing mitotic environment. On the other hand, the ;dissolution' and displacement of PMM clusters from a centric to distal position can be induced by partial dephosphorylation or chromosome unravelling, indicating that these changes reflect the regulated grouping and scrambling of PMM subdomains during cell division. Formation of PMM is prevented by haspin knockdown and leads to delayed exit from mitosis. However, PMM-negative cells do not exhibit major chromosomal defects, suggesting that the local structures formed by PMM chromatin may serve as a ;licensing system' that allows quick clearance through the metaphase-anaphase checkpoint.
Institution and School/Department of submitter: Πανεπιστήμιο Ιωαννίνων. Σχολή Επιστημών Υγείας. Τμήμα Ιατρικής
Keywords: Animals,Antibodies/metabolism,Chromatin/*metabolism,Gene Knockdown Techniques,Histones/chemistry/*metabolism,Humans,Intracellular Signaling Peptides and Proteins/metabolism,Mice,*Mitosis,Phosphorylation,Phosphothreonine/*metabolism,*Protein Processing, Post-Translational,Protein-Serine-Threonine Kinases/metabolism,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization,Time Factors,Transfection
ISSN: 0021-9533
Appears in Collections:Άρθρα σε επιστημονικά περιοδικά ( Ανοικτά)

Files in This Item:
File Description SizeFormat 
Markaki-2009-Phosphorylation of h.pdf1.97 MBAdobe PDFView/Open

 Please use this identifier to cite or link to this item:
  This item is a favorite for 0 people.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.