Determination of DNA cooperativity factor.
نویسندگان
چکیده
The paper presents measurements of the difference in the melting temperature of a colE1 DNA region when it is located inside the DNA helix and at its end. A direct comparison of calculations based on the rigorous theory of helix-coil transition with experimental data for .2 M Na+ (the conditions for fully reversible melting) yielded the value of 2.5-5x10(-5) for the cooperatively factor sigma. We discuss the reversibility of DNA melting and the possibility of applying the "all-or-nothing" concept to the melting of DNA regions.
منابع مشابه
Quantification of Cooperativity in Heterodimer-DNA Binding Improves the Accuracy of Binding Specificity Models.
Many transcription factors (TFs) have the ability to cooperate on DNA elements as heterodimers. Despite the significance of TF heterodimerization for gene regulation, a quantitative understanding of cooperativity between various TF dimer partners and its impact on heterodimer DNA binding specificity models is still lacking. Here, we used a novel integrative approach, combining microfluidics-ste...
متن کاملCooperative DNA Recognition Modulated by an Interplay between Protein-Protein Interactions and DNA-Mediated Allostery
Highly specific transcriptional regulation depends on the cooperative association of transcription factors into enhanceosomes. Usually, their DNA-binding cooperativity originates from either direct interactions or DNA-mediated allostery. Here, we performed unbiased molecular simulations followed by simulations of protein-DNA unbinding and free energy profiling to study the cooperative DNA recog...
متن کاملCooperativity in transcriptional control
Transcription is controlled by promoter-selective factors, which bind to cis-regulatory elements in a specific subset of genes. Regulation by these factors involves direct interactions with the general transcriptional machinery as well as interactions with co-activators and co-repressors. These co-regulators often function by modifying the covalent or non-covalent structure of the chromatin tem...
متن کاملSequence-dependent cooperative binding of p53 to DNA targets and its relationship to the structural properties of the DNA targets
The prime mechanism by which p53 acts as a tumor suppressor is as a transcription factor regulating the expression of diverse downstream genes. The DNA-binding domain of p53 (p53DBD) interacts with defined DNA sites and is the main target for mutations in human primary tumors. Here, we show that the CWWG motif, found in the center of each consensus p53 half-site, is a key player in p53/DNA inte...
متن کاملModels of transcription factor binding: sensitivity of activation functions to model assumptions.
We present three models of how transcription factors (TFs) bind to their specific binding sites on the DNA: a model based on statistical physics, a Markov-chain model and a computational simulation. Comparison of these models suggests that the effect of non-specific binding can be significant. We also investigate possible mechanisms for cooperativity. The simulation model suggests that direct i...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Nucleic acids research
دوره 9 20 شماره
صفحات -
تاریخ انتشار 1981