Preferred Label : AKAP8 in Mitosis Pathway;
NCIt related terms : AKAP95 role in mitosis and chromosome dynamics;
Alternative definition : BIOCARTA: Chromatin packaging of the genome is dynamic, changing with the cell cycle
and with transcriptional regulation. During mitosis, chromatin is condensed for segregation
of chromosomes, while for transcription chromatin is more open. The nuclear matrix,
or scaffold, is a protein network in the nucleus providing structure and regulating
chromatin condensation. Regulated interactions of matrix proteins with each other,
DNA and other factors in different phases of the cell cycle alter the structure and
function of chromatin. AKAP95 (A-kinase anchoring protein) is a nuclear matrix associated
protein that also binds DNA and different proteins during different phases of the
cell cycle. The interaction of AKAP95 with DNA and proteins alters the condensation
and transcription of chromatin. A specific domain of AKAP95 regulates its interaction
with the nuclear matrix and another regulates its association with DNA. One key protein
that AKAP95 interacts with is the cAMP-dependent protein kinase, PKA. AKAP95 binds
to PKA through a PKA RII regulatory subunit, an interaction that requires PKA phosphorylation
by Cdk1. PKA activity and cAMP are reduced during entry into mitosis, but PKA recruited
by AKAP95 to condensed chromosomes is essential to maintain the condensed state. Another
protein recruited by AKAP95 is Eg7, a 150 kD protein recruited during mitotic chromatin
condensation. Eg7 is a part of a multiprotein condensin complex, recruiting another
key component of mitotic chromatin condensation. Modification of the core histones
through phosphorylation regulates chromatin condensation. Histone H3 interacts with
the condensin complex, and is phosphorylated during mitosis. Histone H3 phosphorylation
by Aurora-2 induces chromatin condensation, and dephosphorylation by PP1 promotes
chromatin decondensation for reentry into interphase. AKAP95 may play a role during
the regulation of chromatin structure for transcription during interphase as well.
The interaction of AKAP95 with the p68 RNA helicase recruits this enzyme to the nuclear
matrix during interphase. Other nuclear RNA helicases interact with transcription
factors and cofactors, suggesting that the p68 RNA helicase also may regulate interactions
of transcription complexes. (This definition may be outdated - see the DesignNote.);
NCIt note : The BIOCARTA Definition (ALT_DEFINITION) for this pathway concept was provided by
BioCarta. This property was not created by, nor is it maintained by the NCI Thesaurus
staff. Additionally, BioCarta is no longer updating its pathway data; thus, the BIOCARTA
Definition might be outdated or inaccurate. Please see the Terms and Conditions for
Use at http://www.biocarta.com/.;
Biocarta ID : h_akap95Pathway;
Origin ID : C38979;
UMLS CUI : C1515840;
Semantic type(s)
- has_gene_product_element
- pathway_has_gene_element
