Signal transducing adapter molecule 1 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 ''STAM''
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
This gene was identified by the rapid tyrosine-phosphorylation of its product in response to cytokine stimulation. The encoded protein contains an
SH3 domain
The SRC Homology 3 Domain (or SH3 domain) is a small protein domain of about 60 amino acid residues. Initially, SH3 was described as a conserved sequence in the viral adaptor protein v-Crk. This domain is also present in the molecules of ph ...
and the
immunoreceptor tyrosine-based activation motif An immunoreceptor tyrosine-based activation motif (ITAM) is a conserved sequence of four amino acids that is repeated twice in the cytoplasmic tails of non-catalytic tyrosine-phosphorylated receptors, cell-surface proteins found mainly on immune ce ...
(ITAM). This protein associates with
JAK3 and
JAK2
Janus kinase 2 (commonly called JAK2) is a non-receptor tyrosine kinase. It is a member of the Janus kinase family and has been implicated in signaling by members of the type II cytokine receptor family (e.g. interferon receptors), the GM-CSF ...
kinases via its ITAM region, and is phosphorylated by the
JAK kinases upon
cytokine
Cytokines () are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling.
Cytokines are produced by a broad range of cells, including immune cells like macrophages, B cell, B lymphocytes, T cell, T lymphocytes ...
stimulation, which suggests the function of this protein is as an adaptor molecule involved in the downstream signaling of
cytokine receptors. HGS/HRS (hepatocyte growth factor-regulated tyrosine kinase substrate) has been found to bind and counteract the function of this protein.
STAM1 contains multiple
amino acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins. Only these 22 a ...
sites that are
phosphorylated
In biochemistry, phosphorylation is described as the "transfer of a phosphate group" from a donor to an acceptor. A common phosphorylating agent (phosphate donor) is ATP and a common family of acceptor are alcohols:
:
This equation can be writt ...
and
ubiquitinated.
Interactions
Signal transducing adaptor molecule has been shown to
interact with
*
HGS,
*
Janus kinase 2
Janus kinase 2 (commonly called JAK2) is a non-receptor tyrosine kinase. It is a member of the Janus kinase family and has been implicated in signaling by members of the type II cytokine receptor family (e.g. interferon receptors), the GM-CS ...
.
*
MAP3K1
Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) is a signal transduction enzyme that in humans is encoded by the autosomal ''MAP3K1'' gene.
Function
MAP3K1 (or MEKK1) is a serine/threonine kinase and ubiquitin ligase that performs a ...
,
*
STAMBP,
and
*
TIMM8A.
References
Further reading
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
{{refend