Where does DNA protein binding occur?
In general, proteins bind to DNA in the major groove; however, there are exceptions. Protein–DNA interaction are of mainly two types, either specific interaction, or non-specific interaction.
How do proteins bind to specific DNA sequences?
Proteins recognize a particular sequence by having a surface that is chemically complementary to that of the DNA, forming a series of favorable electrostatic and van der Waals interactions between the protein and the base pairs.
What do binding proteins do in DNA replication?
During DNA replication, SSB molecules bind to the newly separated individual DNA strands, keeping the strands separated by holding them in place so that each strand can serve as a template for new DNA synthesis.
What major forces stabilize a bond between DNA and DNA binding protein?
Formation of hydrogen bonds between amino acid side chain residues of protein and DNA bases stabilizes the protein-DNA interactions (Rohs et al., 2010).
What causes major and minor grooves in DNA?
Double-helical nucleic acid molecules contain two grooves, called the major groove and the minor groove. These grooves arise because the glycosidic bonds of a base pair are not diametrically opposite each other (Figure 27.7).
What are the three DNA binding structures?
Although each of these proteins has unique features, most bind to DNA as homodimers or heterodimers and recognize DNA through one of a small number of structural motifs. The common motifs include the helix-turn-helix, the homeodomain, the leucine zipper, the helix-loop-helix, and zinc fingers of several types.
Which of the following is a major difference between different DNA binding motifs?
Which of the following is a major difference between different DNA-binding motifs? They employ different mechanisms to position and stabilize a recognition alpha helix in the major groove of DNA.
Which of the following is not a DNA binding motif?
Which of the following is a shared property of all DNA binding motifs?
Which of the following is a shared property of all DNA-binding motifs? These DNA-binding motifs share the property of interacting with specific sequences of bases, usually through the major groove of the DNA helix.
How do transcription factors bind to DNA?
Some transcription factors bind to a DNA promoter sequence near the transcription start site and help form the transcription initiation complex. Other transcription factors bind to regulatory sequences, such as enhancer sequences, and can either stimulate or repress transcription of the related gene.
How do transcription factors recognize their binding site on the DNA?
Transcription factors recognize and bind to specific DNA sequences called promotor or enhancer sequences. Other transcription factors called activators target enhancer sequences that initiate the bending of the DNA to allow interaction with the proteins bound to the promoter region. …
Are allosteric proteins that can bind to DNA and stimulate the initiation of transcription?
Positive control is mediated by another class of regulatory, allosteric proteins called activators that can bind to DNA and stimulate the initiation of transcription. Activators are the logical and physical opposites of repressors. Effector molecules can either enhance or decrease activator binding.
What are two potential devices that eukaryotic cells use to regulate transcription?
Two potential devices that eukaryotic cells use to regulate transcription are A) DNA methylation and histone amplification.
What are enhancers and silencers?
Enhancers and Silencers Enhancers have the ability to greatly increase the expression of genes in their vicinity. More recently, elements have been identified that decrease transcription of neighboring genes, and these elements have been called silencers. Extensive analysis of enhancers have detected several features.
What is the function of negative regulator genes?
Negative regulators act to prevent transcription or translation. Examples such as cFLIP suppress cell death mechanisms leading to pathological disorders like cancer, and thus play a crucial role in drug resistance.
What does negative regulation mean?
Negative Regulation. The binding of a specific protein (repressor) inhibits transcription from occurring. DNA bound repressors often act to prevent RNA polymerase from binding to the promoter, or by blocking the movement of RNA polymerase.
Is the lac operon negative or positive control?
The lac operon is a negatively controlled inducible operon, where the inducer molecule is allolactose. In negative repressible operons, transcription of the operon normally takes place. Repressor proteins are produced by a regulator gene, but they are unable to bind to the operator in their normal conformation.
Which is the largest human gene?
What are three functions of DNA?
DNA now has three distinct functions—genetics, immunological, and structural—that are widely disparate and variously dependent on the sugar phosphate backbone and the bases./span>
What are the two major functions of DNA?
DNA serves two important cellular functions: It is the genetic material passed from parent to offspring and it serves as the information to direct and regulate the construction of the proteins necessary for the cell to perform all of its functions.
What is the primary job of DNA see Section 13.1 page?
Use the genetic code (Table 13-3) to translate the following strand of DNA: TACACCTAA. What is the primary job of DNA? It provides blueprints for proteins.
What is the relationship between enzymes and DNA?
An enzyme is a molecule that speeds up a reaction. In the case of DNA reproduction, enzymes not only speed up the reaction, they are necessary for DNA reproduction. Recall that DNA is a long strand with a many repeating base pairs. In order for DNA to reproduce, the base pairs must be split apart.
What DNA mean?