What is a transcription factor DNA binding motif?
Transcription factors (TFs) are proteins with DNA binding activity that are involved in the regulation of transcription. A TF has binding preferences to a specific set of DNA sequences referred to as a “binding motif.” TFs have different binding affinities for sequences forming their binding motif set.
What happens when a transcription factor is phosphorylated?
Phosphorylation is a prevalent mechanism by which transcription factors are regulated in response to cellular signals. In addition to its role as a cAMP-responsive activator, CREB seems to be phosphorylated and to promote cellular gene expression in response to growth factor signals.
How do you characterize a transcription factor?
TFs are sequence-specific DNA-binding proteins and represent 3–6% of the human genome (Venter et al., 2001), which act as transcriptional activators and repressors. To regulate transcription, TFs bind to specific DNA sequences, typically 6–12 base pairs (bp), called the response element (RE).
What is an architectural transcription factor?
Architectural proteins influence structural aspects of enhanceosomes through protein:DNA as well as protein:protein interactions. These families of proteins interact with specific structural features of DNA, modulate transcription factor binding to DNA, and interact directly with other transcription factors.
What does a transcription factor do?
Transcription factors are proteins involved in the process of converting, or transcribing, DNA into RNA. Transcription factors include a wide number of proteins, excluding RNA polymerase, that initiate and regulate the transcription of genes.
What is an example of a transcription factor?
The Hox transcription factor family, for example, is important for proper body pattern formation in organisms as diverse as fruit flies to humans. Another example is the transcription factor encoded by the sex-determining region Y (SRY) gene, which plays a major role in determining sex in humans.
What happens when a gene is phosphorylated?
Phosphorylation alters the structural conformation of a protein, causing it to become activated, deactivated, or modifying its function. Approximately 13000 human proteins have sites that are phosphorylated. The reverse reaction of phosphorylation is called dephosphorylation, and is catalyzed by protein phosphatases.
How does methylation affect gene expression?
DNA methylation regulates gene expression by recruiting proteins involved in gene repression or by inhibiting the binding of transcription factor(s) to DNA. As a consequence, differentiated cells develop a stable and unique DNA methylation pattern that regulates tissue-specific gene transcription.
What is epigenetic expression?
Epigenetics has been defined as ‘the study of mitotically (and potentially meiotically) heritable alterations in gene expression that are not caused by changes in DNA sequence’ (Waterland, 2006).
How do transcription factors find their targets?
Transcription factors (which are described in the video) have to be able to first scan the genome so they can find their target sites and then bind there, which will turn genes on or off. It’s known that they can also randomly attach to the genome non-specifically.
What is meant by phosphorylated?
Phosphorylation: A biochemical process that involves the addition of phosphate to an organic compound. Examples include the addition of phosphate to glucose to produce glucose monophosphate and the addition of phosphate to adenosine diphosphate (ADP) to form adenosine triphosphate (ATP).
How does methylation affect transcription?
In an interestingly coordinated process, proteins that bind to methylated DNA also form complexes with the proteins involved in deacetylation of histones. Therefore, when DNA is methylated, nearby histones are deacetylated, resulting in compounded inhibitory effects on transcription.
What does KLF2 stand for?
Krüppel-like Factor 2 (KLF2), also known as lung Krüppel-like Factor (LKLF), is a protein that in humans is encoded by the KLF2 gene on chromosome 19.
What are the structural features of the KLF2 protein?
KLF2 also exhibits these structural features. The mRNA transcript is approximately 1.5 kilobases in length, and the 37.7 kDa protein contains 354 amino acids. KLF2 also shares some homology with EKLF at the N-terminus with a proline -rich region presumed to function as the transactivation domain.
Why does KLF2 have zinc fingers?
The zinc fingers enable all KLF proteins to bind to CACCC gene promoters, so although they may complete varied functions (due to lack of homology away from the zinc fingers), they all recognize similar binding domains. KLF2 also exhibits these structural features.
Is KLF2 a Krüppel-like factor?
By transactivation assay in mouse fibroblasts, KLF2 was also noticed to bind to the β-globin gene promoter containing the CACCC sequence shown to be the binding site for EKLF, confirming KLF2 as a member of the Krüppel-like Factor family. Since then, many other KLF proteins have been discovered.