|
||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Article |
Address correspondence to Philippe Collas, Institute of Medical Biochemistry, P.O. Box 1112 Blindern, University of Oslo, Oslo 0317, Norway. Tel.: 47-2285-1066. Fax: 47-2285-1058. E-mail: philippe.collas{at}basalmed.uio.no
HA95 is a chromatin-associated protein that interfaces the nuclear envelope (NE) and chromatin. We report an interaction between HA95 and the inner nuclear membrane protein lamina-associated polypeptide (LAP) 2ß, and a role of this association in initiation of DNA replication. Precipitation of GSTLAP2ß fusion proteins and overlays of immobilized HA95 indicate that a first HA95-binding region lies within amino acids 137242 of LAP2ß. A second domain sufficient to bind HA95 colocalizes with the lamin Bbinding domain of LAP2ß at residues 299373. HA95LAP2ß interaction is not required for NE formation. However, disruption of the association of HA95 with the NH2-terminal HA95-binding domain of LAP2ß abolishes the initiation, but not elongation, of DNA replication in purified G1 phase nuclei incubated in S-phase extract. Inhibition of replication initiation correlates with proteasome-mediated proteolysis of Cdc6, a component of the prereplication complex. Rescue of Cdc6 degradation with proteasome inhibitors restores replication. We propose that an interaction of LAP2ß, or LAP2 proteins, with HA95 is involved in the control of initiation of DNA replication.
Key Words: chromosome; lamina-associated polypeptide; HA95; nuclear envelope; replication
Related Article
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
J. Cell Biol. 2003 160: 153.
This article has been cited by other articles:
|
|