Energetic contribution of residues in the Runx1 Runt domain to DNA binding.
Core-binding factors (CBFs) are a small family of heterodimeric transcription factors that play critical roles in hematopoiesis and in the development of bone, stomach epithelium, and proprioceptive neurons. Mutations in CBF genes are found in leukemias, bone disorders, and gastric cancer. CBFs consist of a DNA-binding CBF alpha subunit and a non-DNA-binding CBF beta subunit. DNA binding and heterodimerization with CBF beta are mediated by the Runt domain in CBF alpha. Here we report an alanine-scanning mutagenesis study of the Runt domain that targeted amino acids identified by structural studies to reside at the DNA or CBF beta interface, as well as amino acids mutated in human disease. We determined the energy contributed by each of the DNA-contacting residues in the Runt domain to DNA binding both in the absence and presence of CBF beta. We propose mechanisms by which mutations in the Runt domain found in hematopoietic and bone disorders affect its affinity for DNA.
Li
Zhe
Z
Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire 03755, USA.
Yan
Jiangli
J
Matheny
Christina J
CJ
Corpora
Takeshi
T
Bravo
Jerónimo
J
Warren
Alan J
AJ
Bushweller
John H
JH
Speck
Nancy A
NA
D000409:Alanine / Q000737:chemistry; D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D050676:Core Binding Factor Alpha 2 Subunit; D050657:Core Binding Factor alpha Subunits; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D019281:Dimerization; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008954:Models, Biological; D008958:Models, Molecular; D016296:Mutagenesis; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D011485:Protein Binding; D011489:Protein Denaturation; D017434:Protein Structure, Tertiary; D011518:Proto-Oncogene Proteins; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D014508:Urea / Q000494:pharmacology
D000596:Amino Acids; D050676:Core Binding Factor Alpha 2 Subunit; D050657:Core Binding Factor alpha Subunits; D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; C493726:Runx1 protein, mouse; D014157:Transcription Factors; C406688:core binding factor alpha; D014508:Urea; D004247:DNA; D000409:Alanine