Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.11.13 (
protein kinase C
)
49,245
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The nuclear envelope mediates key functions by interacting with chromatin. We recently reported an interaction between the chromatin- and nuclear matrix-associated protein
HA95
and the inner nuclear membrane integral protein LAP2beta, implicated in initiation of DNA replication (Martins et al. (2003) J. Cell Biol. 160, 177-188). Here, we show that in vitro, interaction between
HA95
and LAP2beta is modulated by cAMP signaling via PKA. Exposure of an anti-
HA95
immune precipitate from interphase HeLa cells to a mitotic extract promotes ATP-dependent release of LAP2beta from the
HA95
complex. This coincides with Ser and Thr phosphorylation of
HA95
and LAP2beta. Inhibition of PKA with PKI abolishes phosphorylation of
HA95
and dissociation of LAP2beta from
HA95
, although LAPbeta remains phosphorylated. Antagonizing cAMP signaling in mitotic extract also abolishes the release of LAP2beta from
HA95
; however, disrupting PKA anchoring to A-kinase anchoring proteins has no effect. Inhibition of CDK activity in the extract greatly reduces LAP2beta phosphorylation but does not prevent LAP2beta release from
HA95
. Inhibition of
PKC
, MAP kinase, or CaM kinase II does not affect mitotic extract-induced dissociation of LAP2beta from
HA95
. PKA phosphorylates
HA95
but not LAP2beta in vitro and elicits a release of LAP2beta from
HA95
. CDK1 or
PKC
phosphorylates LAP2beta within the
HA95
complex, but neither kinase induces LAP2beta release. Our results indicate that in vitro, the interaction between
HA95
and LAP2beta is influenced by a PKA-mediated phosphorylation of
HA95
rather than by CDK1- or
PKC
-mediated phosphorylation of LAP2beta. This suggests an additional level of regulation of a chromatin-nuclear envelope interaction in dividing cells.
...
PMID:In vitro modulation of the interaction between HA95 and LAP2beta by cAMP signaling. 1295 Jan 72
