1. NUCLEAR RECEPTORS NOMENCLATURE COMMITTEE
A unified nomenclature system for the nuclear receptor superfamily.
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2. NISHIKAWA, J-I., KITAURA, M., IMAGAWA, M. AND NISHIHARA, T.
Vitamin D receptor contains multiple dimerisation interfaces that
are functionally different.
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Human androgen receptor expressed in HeLa cells activates transcription
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4. MING-JER, T. AND O'MALLEY, B.
Molecular mechanisms of action of steroid/thyroid receptor superfamily
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5. BEATO, M., HERRLICH, P. AND SCHUTZ, G.
Steroid hormone receptors: many actors in search of a plot.
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Steroid or nuclear hormone receptors (NRs) constitute an important super-
family of transcription regulators that are involved in widely diverse
physiological functions, including control of embryonic development, cell
differentiation and homeostasis . Members of the superfamily include the
steroid hormone receptors and receptors for thyroid hormone, retinoids,
1,25-dihydroxy-vitamin D3 and a variety of other ligands. The proteins
function as dimeric molecules in nuclei to regulate the transcription of
target genes in a ligand-responsive manner [1-5]. In addition to C-terminal
ligand-binding domains, these nuclear receptors contain a highly-conserved,
N-terminal zinc-finger that mediates specific binding to target DNA
sequences, termed ligand-responsive elements. In the absence of ligand,
steroid hormone receptors are thought to be weakly associated with nuclear
components; hormone binding greatly increases receptor affinity.
NRs are extremely important in medical research, a large number of them
being implicated in diseases such as cancer, diabetes, hormone resistance
syndromes, etc. . While several NRs act as ligand-inducible transcription
factors, many do not yet have a defined ligand and are accordingly termed
"orphan" receptors. During the last decade, more than 300 NRs have been
described, many of which are orphans, which cannot easily be named due to
current nomenclature confusions in the literature. However, a new system
has recently been introduced in an attempt to rationalise the increasingly
complex set of names used to describe superfamily members .
The glucocorticoid receptor consists of 3 functional and structural
domains: an N-terminal (modulatory) domain; a DNA binding domain that
mediates specific binding to target DNA sequences (ligand-responsive
elements); and a hormone binding domain. The N-terminal domain is unique
to the glucocorticoid receptors; it spans the first 440 residues, and is
primarily responsible for transcriptional activation. The smaller (around
65 residues), highly-conserved central portion of the protein is the DNA
binding domain, which plays a role in DNA binding specificity, homo-
dimerisation and in interactions with other proteins. The hormone binding
domain comprises approximately 250 residues at the C-terminus of the
receptor. This domain mediates receptor activity via interaction with heat
shock proteins and cyclophilins, or with hormone. For more information, see
the GRR resource at http://biochem1.basic-sci.georgetown.edu/GRR/GRR.html.
GLCORTICOIDR is a 6-element fingerprint that provides a signature for the
glucocorticoid receptors. The fingerprint was derived from an initial
alignment of 5 sequences: the motifs span the N-terminal modulatory domain
preceding the highly-conserved zinc-binding region shared by the steroid
hormone receptor family. Two iterations on OWL28.0 were required to reach
convergence, at which point a true set comprising 9 sequences was
identified. Two partial matches were also found (GCR_SHEEP and S76851),
both of which are fragments.
An update on SPTR37_9f identified a true set of 11 sequences.