Biophysical characterization of interactions between the core binding factor alpha and beta subunits and DNA.
Core binding factors (CBFs) play key roles in several developmental pathways and in human disease. CBFs consist of a DNA binding CBFalpha subunit and a non-DNA binding CBFbeta subunit that increases the affinity of CBFalpha for DNA. We performed sedimentation equilibrium analyses to unequivocally establish the stoichiometry of the CBFalpha:beta:DNA complex. Dissociation constants for all four equilibria involving the CBFalpha Runt domain, CBFbeta, and DNA were defined. Conformational changes associated with interactions between CBFalpha, CBFbeta, and DNA were monitored by nuclear magnetic resonance and circular dichroism spectroscopy. The data suggest that CBFbeta 'locks in' a high affinity DNA binding conformation of the CBFalpha Runt domain.
Tang
Y Y
YY
Department of Biochemistry, Dartmouth Medical School, Hanover, NH 03755, USA.
Crute
B E
BE
Kelley
J J
JJ
Huang
X
X
Yan
J
J
Shi
J
J
Hartman
K L
KL
Laue
T M
TM
Speck
N A
NA
Bushweller
J H
JH
D000818:Animals; D002151:Calorimetry; D002942:Circular Dichroism; D050676:Core Binding Factor Alpha 2 Subunit; D050657:Core Binding Factor alpha Subunits; D004247:DNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D019281:Dimerization; D008958:Models, Molecular; D008970:Molecular Weight; D019906:Nuclear Magnetic Resonance, Biomolecular; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011518:Proto-Oncogene Proteins; D013816:Thermodynamics; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D014461:Ultracentrifugation
D050676:Core Binding Factor Alpha 2 Subunit; D050657:Core Binding Factor alpha Subunits; D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; D050656:Transcription Factor AP-2; D014157:Transcription Factors; C406688:core binding factor alpha; D004247:DNA