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30/03/2019

What does transcription factor dimerization do?

What does transcription factor dimerization do?

Dimerization of transcription factors allows combinatorial control. Combinatorial control such as this may provide for tissue-specific gene expression in the absence of tissue-specific transcription factors. Only the combination of proteins needs to be tissue-specific.

Which domains can be found on transcription factor proteins?

Transcription factors are modular in structure and contain the following domains:

  • DNA-binding domain (DBD), which attaches to specific sequences of DNA (enhancer or promoter.
  • Activation domain (AD), which contains binding sites for other proteins such as transcription coregulators.

What happens when transcription factors are phosphorylated?

Phosphorylation of the inhibitor liberates the transcription factor allowing for DNA binding. The active transcription factor is bound to DNA, and its inhibitor is inactive. Phosphorylation of the inhibitor stimulates its interaction with the DBD, resulting in inhibition of DNA binding.

What are the three domains found on most transcription factor dimers?

Figure 12.1. Structure of a prototypical transcription factor (TF). An inducible TF usually displays four different structural domains: a DNA binding domain (mandatory), a transactivation domain (mandatory), a dimerization domain, and a ligand binding site.

What is dimerization reaction?

A dimerization is an addition reaction in which two molecules of the same compound react with each other to give the adduct.

What is the function of transcription factors?

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 functional domains are found in transcription factors?

Transcription factors are modular in nature in all organisms. In general, they have a DNA binding domain, one or more transcription activation and/or repressor domain, and often a dimerization domain. In many cases, transcription factors also have other protein-protein interaction domain(s).

What do all transcription factors contain?

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 phosphorylation increase transcription?

Phosphorylation of TCF at a cluster of sites located next to its carboxyl terminus stimulates its transactivation function, probably by enhancing its ability to interact with the basal transcription machinery. This pathway leads to rapid activation of c-fos transcription.

What is a dimerization domain?

The dimerization domain of the LBD has been proposed to form a helical structure presenting a hydrophobic surface formed by the repetition of nine heptad motifs containing hydrophobic residues at positions 1 and 8, and hydrophobic or charged amino acids with hydrophobic side chains at position 5 (94).

What is Dimerisation process?

What is dimerization? It is a process where two molecules of similar chemical composition come together to form a single polymer known as a dimer. Where does dimerization occur? In the nucleus, hormone receptors, acting as transcription factors, form dimers to increase stability and improve binding to DNA.

What is the structure of the dimerization domain?

  Forms homo- or heterodimers.   Dimerization domain has a four- helix bundle structure.   Extension of one of the α-helices from DNA binding domain binds the major groove of DNA.   Examples of HLH transcription factors

How does dimerization of the tyrosine kinase receptor work?

Dimerization leads to transphosphorylation of the tyrosine kinase domains of the receptor with signaling via downstream intracellular pathways leading to cell activation and proliferation. From: Her2-Positive Breast Cancer, 2019

When does dimerization of membrane protein interfaces occur?

Dimerization of membrane protein interfaces occurs during membrane protein folding and cell receptor signaling.

Is the dimerization model for RPTP regulation universal?

The dimerization model for RPTP regulation may not be a universal mechanism employed by all RPTPs. The crystal structures of the membrane-proximal phosphatase domain of RPTPμ and the tandem phosphatase domains of LAR failed to show dimer formation through the inhibitory wedge region [ 7,8 ].