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
.
What are the 3 structural motifs in DNA-binding proteins?
It has been observed that many known DNA-binding proteins have one of a small number of distinct structural motifs that play a key role in binding DNA (2). We focus on three motifs:
the helix–turn–helix (HTH) motif, the helix–hairpin–helix (HhH) motif and the helix–loop–helix (HLH) motif.
What are the major DNA-binding motifs and what is their function?
The DNA binding proteins have a specific folding pattern which is made of repeated nucleotide sequences called as DNA binding motifs. These motifs permit the binding of DNA binding proteins such as
transcription factors to the target sequence
. It is composed of recognition region and stabilization region.
Are there different types of DNA-binding proteins?
DNA-binding proteins can incorporate such domains as the zinc finger, the
helix-turn-helix
, and the leucine zipper (among many others) that facilitate binding to nucleic acid. There are also more unusual examples such as transcription activator like effectors.
What are the three DNA-binding structures transcription factors )?
The most common GTFs are
TFIIA, TFIIB, TFIID
(see also TATA binding protein), TFIIE, TFIIF, and TFIIH. The preinitiation complex binds to promoter regions of DNA upstream to the gene that they regulate.
Which of the following is not a DNA-binding motif?
5. Which among the following is not a DNA-binding motif? Explanation:
Homeobox
is not a DNA-binding motif. The DNA sequence that encodes homeodomain is known as the homeobox.
Which of the following is a DNA-binding motif?
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
.
Why are DNA binding proteins dimeric?
The function of CAP is
to bind to DNA to assist the binding of RNA polymerase to specific promoter regions
. It is a dimer of two identical 209-residue chains.
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.
Why are DNA binding proteins important?
DNA-binding proteins have a
central role in all aspects of genetic activity within an organism
, such as transcription, packaging, rearrangement, replication and repair.
What is a common DNA binding domain?
A DNA-binding domain (DBD) is an
independently folded protein domain
that contains at least one structural motif that recognizes double- or single-stranded DNA. A DBD can recognize a specific DNA sequence (a recognition sequence) or have a general affinity to DNA.
Why do motifs occur in DNA?
Sequence motifs are short, recurring patterns in DNA
that are presumed to have a biological function
. Often they indicate sequence-specific binding sites for proteins such as nucleases and transcription factors (TF).
Which item is a common DNA binding motif quizlet?
Among the most common DNA-binding domains are the
zinc finger domains
, helix-turn-helix, leucine zipper, homeobox domains, and basic helix-loop-helix structure.
How do you identify a DNA binding protein?
DNA-binding proteins can be identified by many experimental techniques such as
chromatin immunoprecipitation on microarrays
, X-ray crystallography and nuclear magnetic resonance (NMR). However, the experimental techniques to recognize DNA-binding proteins are labor-intensive and time-consuming.
What are the receptors for DNA-binding proteins?
The majority of
nuclear receptors
have two highly-conserved Cys
4
zinc fingers through which they bind DNA, and some nuclear receptors, such as the GCR, can also bind RNA through these domains
1
. Other types of zinc fingers are also enriched in DRBPs, such as the RanBP2-type.
What are 2 features of DNA that helix turn helices can bind to?
It binds to
the major groove of DNA through a series of hydrogen bonds and various Van der Waals interactions with exposed bases
. The other α helix stabilizes the interaction between protein and DNA, but does not play a particularly strong role in its recognition.
