Tabela com principais espec.
|Species Reactivity||Key Applications||Host||Format||Antibody Type|
|Description||Anti-phospho-CENP-A (Ser7) Antibody|
|Overview||CENP-A is a variant version of histone H3 found only at centromeres. It is phosphorylated at serine 7 during mitosis.|
|Presentation||0.1M Tris-glycine, pH 7.4, 0.15M NaCl, 0.05% sodium azide before the addition of glycerol to 30%|
|Application||Detect phospho-CENP-A (Ser7) with Anti-phospho-CENP-A (Ser7) Antibody (Rabbit Polyclonal Antibody), that has been shown to work in WB.|
|Safety Information according to GHS|
|Storage and Shipping Information|
|Storage Conditions||2 years at -20°C|
|Material Size||200 µg|
|Título||Número do lote|
|Anti-phospho-CENP-A (Ser7) - 20483||20483|
|Visão geral das referências||Pub Med ID|
|Cell-cycle-dependent structural transitions in the human CENP-A nucleosome in vivo. |
Bui, M; Dimitriadis, EK; Hoischen, C; An, E; Quénet, D; Giebe, S; Nita-Lazar, A; Diekmann, S; Dalal, Y
Cell 150 317-26 2012
In eukaryotes, DNA is packaged into chromatin by canonical histone proteins. The specialized histone H3 variant CENP-A provides an epigenetic and structural basis for chromosome segregation by replacing H3 at centromeres. Unlike exclusively octameric canonical H3 nucleosomes, CENP-A nucleosomes have been shown to exist as octamers, hexamers, and tetramers. An intriguing possibility reconciling these observations is that CENP-A nucleosomes cycle between octamers and tetramers in vivo. We tested this hypothesis by tracking CENP-A nucleosomal components, structure, chromatin folding, and covalent modifications across the human cell cycle. We report that CENP-A nucleosomes alter from tetramers to octamers before replication and revert to tetramers after replication. These structural transitions are accompanied by reversible chaperone binding, chromatin fiber folding changes, and previously undescribed modifications within the histone fold domains of CENP-A and H4. Our results reveal a cyclical nature to CENP-A nucleosome structure and have implications for the maintenance of epigenetic memory after centromere replication.
|MAP kinase regulation of the mitotic spindle checkpoint. |
Eva M Eves,Marsha Rich Rosner
Methods in molecular biology (Clifton, N.J.) 661 2010
Maintaining the integrity of the cell cycle is critical for ensuring that cells only undergo DNA replication and proliferation under controlled conditions in response to discrete stimuli. One mechanism by which the fidelity of this process is guaranteed is through the activation of cell cycle checkpoints. The mitotic spindle checkpoint, which is regulated by Aurora B kinase, ensures proper kinetochore attachment to chromosomes leading to equal distribution of chromosomes to daughter cells. We demonstrated that the mitogen-activated protein kinase (MAPK) cascade regulates mitotic progression and the spindle checkpoint. As demonstrated by immunofluorescence at kinetochores, depletion of Raf Kinase Inhibitory Protein (RKIP), an inhibitor of Raf/MEK/ERK signaling, causes an increase in MAPK activity that inhibits Aurora B kinase activity. By monitoring mitotic index and transit time from nuclear envelope breakdown to anaphase, we demonstrated that RKIP depletion leads to a defective spindle checkpoint and genomic instability, particularly in response to drugs that disrupt microtubule function.
|CENP-A is phosphorylated by Aurora B kinase and plays an unexpected role in completion of cytokinesis. |
Zeitlin, S G, et al.
J. Cell Biol., 155: 1147-57 (2001) 2001
Aurora B is a mitotic protein kinase that phosphorylates histone H3, behaves as a chromosomal passenger protein, and functions in cytokinesis. We investigated a role for Aurora B with respect to human centromere protein A (CENP-A), a centromeric histone H3 homologue. Aurora B concentrates at centromeres in early G2, associates with histone H3 and centromeres at the times when histone H3 and CENP-A are phosphorylated, and phosphorylates histone H3 and CENP-A in vitro at a similar target serine residue. Dominant negative phosphorylation site mutants of CENP-A result in a delay at the terminal stage of cytokinesis (cell separation). The only molecular defects detected in analysis of 22 chromosomal, spindle, and regulatory proteins were disruptions in localization of inner centromere protein (INCENP), Aurora B, and a putative partner phosphatase, PP1gamma1. Our data support a model where CENP-A phosphorylation is involved in regulating Aurora B, INCENP, and PP1gamma1 targeting within the cell. These experiments identify an unexpected role for the kinetochore in regulation of cytokinesis.