Cytohesin-1 formerly known as Pleckstrin homology, Sec7 and coiled/coil domains 1 (PSCD1) is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''CYTH1''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
Function
Cytohesin-1 (CYTH1) is a member of the cytohesin family. Members of this family have identical structural organization that consists of an
N-terminal
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the amin ...
coiled-coil
A coiled coil is a structural motif in proteins in which two to seven alpha-helices are coiled together like the strands of a rope. ( Dimers and trimers are the most common types.) They have been found in roughly 5-10% of proteins and have a v ...
motif, a central Sec7 domain, and a
C-terminal
The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, carboxy tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When t ...
pleckstrin homology
Pleckstrin homology domain (PH domain) or (PHIP) is a protein domain of approximately 120 amino acids that occurs in a wide range of proteins involved in intracellular signaling or as constituents of the cytoskeleton.
This domain can bind phosph ...
(PH) domain. The coiled-coil motif is involved in
homodimerization, the Sec7 domain contains
guanine-nucleotide exchange protein (GEP) activity, and the PH domain interacts with
phospholipid
Phospholipids are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids typ ...
s and is responsible for association of CYTHs with membranes. Members of this family appear to mediate the regulation of
protein sorting and membrane trafficking. The CYTH1 is highly expressed in
natural killer
Nature is an inherent character or constitution, particularly of the ecosphere or the universe as a whole. In this general sense nature refers to the laws, elements and phenomena of the physical world, including life. Although humans are par ...
and peripheral
T cells
T cells (also known as T lymphocytes) are an important part of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their ce ...
, and regulates the adhesiveness of integrins at the plasma membrane of
lymphocyte
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include T cells (for cell-mediated and cytotoxic adaptive immunity), B cells (for humoral, antibody-driven adaptive immunity), an ...
s. CYTH1 protein is 83% homologous to
CYTH2.
Interactions
CYTH1 has been shown to
interact with:
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ARFRP1,
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CD18
In molecular biology, CD18 (Integrin beta chain-2) is an integrin beta chain protein that is encoded by the '' ITGB2'' gene in humans. Upon binding with one of a number of alpha chains, CD18 is capable of forming multiple heterodimers, which play ...
,
and
*
TRIM23.
References
Further reading
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{{PDB Gallery, geneid=9267