Is a leucine zipper a helix-turn-helix motif?

Many motifs are involved in the binding of DNA. These motifs include the helix-turn-helix (HTH), helix-loop-helix (HLH), zinc fingers, and leucine zippers.

What does the helix-turn-helix motif do?

The helix-turn-helix (HTH) motif is commonly found in proteins that bind DNA, especially transcription factors. In recognizing DNA, the last helix of the HTH motif that is commonly referred to as the recognition helix inserts into the DNA major groove to mediate base-specific DNA recognition.

What is the leucine zipper motif?

The leucine zipper (ZIP) motif consists of a periodic repetition of a leucine residue at every seventh position (heptad repeat) and forms an α-helical conformation, which facilitates dimerisation and in some cases higher oligomerisation of proteins by forming a parallel helix–helix association stabilised by formation …

Is a leucine zipper?

Leucine zippers are α-helices that contain a leucine residue every seventh amino acid. This motif is found in many eukaryotic transcription factors. Zinc fingers consist of 25-30 amino acids surrounding a single zinc atom, which is coordinated by two cysteines, which are very close to short α-helices.

Is a leucine zipper a domain?

Sequence and structure Leucine zipper is created by the dimerization of two specific alpha helix monomers bound to DNA. The leucine zipper is formed by amphipathic interaction between two ZIP domains. The ZIP domain is found in the alpha-helix of each monomer, and contains leucines, or leucine-like amino acids.

How do leucine zippers interact with DNA?

The Leucine Zipper and the Basic DNA-Binding Domain (bZIP) In turn, such dimerization results in the correct protein structure for DNA binding by the adjacent highly basic region that can interact directly with the acidic DNA.

What is homeodomain protein?

The homeodomain is a highly conserved 60‐amino‐acid protein domain that is encoded by the homeobox and is found in organisms as diverse as mammals, insects, plants and yeast. Homeodomains function as DNA binding domains and are found in many transcription factors that control development and cell fate decisions.

What is leucine zipper structure?

What is basic leucine zipper transcription factor?

The basic leucine zipper (bZIP) transcription factors are sequence-specific DNA-binding proteins that regulate transcription. They are characterized by a 60-80 amino acid bZIP domain: a basic DNA binding domain followed by a leucine zipper dimerization domain. (Adapted from FBrf0152056).

How the leucine zipper is held together?

A leucine zipper is formed by two α helices, one from each monomer. The helices are held together by hydrophobic interactions between leucine residues, which are located on one side of each helix.