Answer:
Explanation:
Nuclear receptors are a type of protein that functions as an intracellular steroid and thyroid hormone receptor. The interaction of these hormones in conjunction with nuclear receptors changes the pattern of gene expression, allowing certain genes to be transcribed while others are silenced.
As a consequence, unique mRNA translation products, proteins, and, in most cases, enzymes are generated. Nuclear receptors connect to DNA directly and control the expression of certain genes, regulating the organisms growth, homeostasis, and metabolism.
The following domains are found in a normal nuclear receptor:
The amino-terminal activation domain contains the transcriptional activation mechanism and is strongly variable in sequence (AF1). The recruiting of coregulators is the domains key feature.
⇒ Activation function 1 (AF1); Coregulator recruitment
DNA binding domain: It is amongst the most closely conserved centrally located domains, with two zinc fingers that attach to specific DNA sequences known as hormone reaction components (HRE).
⇒ nine conserved cysteine residues; zinc finger domain; center of the receptor.
The hiinge domain serves as a versatile connection between the DNA binding and ligand-binding domains. It has a nuclear localization signal in it. ⇒ Nuclear localization signal
Ligand binding domain: The sequence of the ligand-binding domain is moderately conserved throughout nuclear receptors. It denotes the carboxyl-terminal end of a ligand domain. It has hydrophobic steroid-binding pockets that draw the hormone and AF2 activation domains. It also attaches to proteins that serve as coactivators and corepressors.
⇒ binding of corepressor proteins; steroid-binding hydrophobic pocket; AF2 activation domain; binds coactivators; carboxyl-terminal end
