2odg
Complex of barrier-to-autointegration factor and LEM-domain of emerin
OverviewOverview
The barrier-to-autointegration factor BAF binds to the LEM domain (Em(LEM)) of the nuclear envelope protein emerin and plays an essential role in the nuclear architecture of metazoan cells. In addition, the BAF(2) dimer bridges and compacts double-stranded DNA nonspecifically via two symmetry-related DNA binding sites. In this article we present biophysical and structural studies on a complex of BAF(2) and Em(LEM). Light scattering, analytical ultracentrifugation, and NMR indicate a stoichiometry of one molecule of Em(LEM) bound per BAF(2) dimer. The equilibrium dissociation constant (K(d)) for the interaction of the BAF(2) dimer and Em(LEM), determined by isothermal titration calorimetry, is 0.59 +/- 0.03 microm. Z-exchange spectroscopy between corresponding cross-peaks of the magnetically non-equivalent subunits of the BAF(2) dimer in the complex yields a dissociation rate constant of 78 +/- 2s(-1). The solution NMR structure of the BAF(2)-Em(LEM) complex reveals that the LEM and DNA binding sites on BAF(2) are non-overlapping and that both subunits of the BAF(2) dimer contribute approximately equally to the Em(LEM) binding site. The relevance of the implications of the structural and biophysical data on the complex in the context of the interaction between the BAF(2) dimer and Em(LEM) at the nuclear envelope is discussed.
About this StructureAbout this Structure
2ODG is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
Solution NMR structure of the barrier-to-autointegration factor-Emerin complex., Cai M, Huang Y, Suh JY, Louis JM, Ghirlando R, Craigie R, Clore GM, J Biol Chem. 2007 May 11;282(19):14525-35. Epub 2007 Mar 13. PMID:17355960 Page seeded by OCA on Sun May 4 10:40:17 2008