Stimulus-specific Interaction between Activator-Coactivator Cognates Revealed with a Novel Complex-specific Antiserum*

التفاصيل البيبلوغرافية
العنوان:	Stimulus-specific Interaction between Activator-Coactivator Cognates Revealed with a Novel Complex-specific Antiserum*
المؤلفون:	Wagner, Brandee L., Bauer, Anton, Schütz, Günther, Montminy, Marc
المصدر:	Journal of Biological Chemistry; March 2000, Vol. 275 Issue: 12 p8263-8266, 4p
مستخلص:	A number of second messenger pathways propagate inductive signals via protein-protein interactions that are phosphorylation-dependent. The second messenger, cAMP, for example, promotes cellular gene expression via the protein kinase A-mediated phosphorylation of cAMP-response element-binding protein (CREB) at Ser133, and this modification in turn stimulates the association of CREB with the co-activator, CREB-binding protein (CBP). The solution structure of the CREB·CBP complex, using relevant interaction domains, kinase inducible domain and kinase-induced domain interacting domain, referred to as KID and KIX, respectively, shows that KID undergoes a coil to helix transition, upon binding to KIX, that stabilizes complex formation. Whether such changes occur in the context of the full-length CREB and CBP proteins, however, is unclear. Here we characterize a novel antiserum that specifically binds to the CREB·CBP complex but to neither protein individually. Epitope mapping experiments demonstrate that the CREB·CBP antiserum detects residues in KID that undergo a conformational change upon binding to KIX. The ability of this antiserum to recognize full-length CREB·CBP complexes in a phospho-(Ser133)-dependent manner demonstrates that the structural transition observed with the isolated KID domain also occurs in the context of the full-length CREB protein. To our knowledge, this is the first report documenting formation of endogenous cellular protein-protein complexes in situ.
قاعدة البيانات:	Supplemental Index

الوصف
تدمد:	00219258 1083351X
DOI:	10.1074/jbc.275.12.8263