ELMO (protein)
Encyclopedia
ELMO is a family of related proteins (~82 kDa) involved in intracellular
signalling
networks. These proteins have no intrinsic catalytic
activity and instead function as adaptors
which can regulate the activity of other proteins through their ability to mediate protein-protein interactions.
This family contains three paralogous isoforms:
of the C. elegans
protein CED-12
. All isoforms contain a series of armadillo repeats
, which begin at the N-terminus and extend around two thirds of the way along the protein, as well as a C-terminal proline
-rich motif and a central PH domain. They function as part of a protein complex
with Dock180-related proteins to form a bipartite guanine nucleotide exchange factor
for Rac
(a member of the Rho family of small G proteins). The Dock180-ELMO interaction requires the ELMO PH domain and also involves binding of the ELMO proline-rich motif to the Dock180 SH3 domain
.
Intracellular
Not to be confused with intercellular, meaning "between cells".In cell biology, molecular biology and related fields, the word intracellular means "inside the cell".It is used in contrast to extracellular...
signalling
Cell signaling
Cell signaling is part of a complex system of communication that governs basic cellular activities and coordinates cell actions. The ability of cells to perceive and correctly respond to their microenvironment is the basis of development, tissue repair, and immunity as well as normal tissue...
networks. These proteins have no intrinsic catalytic
Biocatalysis
Biocatalysis is the use of natural catalysts, such as protein enzymes, to perform chemical transformations on organic compounds. Both enzymes that have been more or less isolated and enzymes still residing inside living cells are employed for this task....
activity and instead function as adaptors
Adaptor protein
Signal transducing adaptor proteins are proteins which are accessory to main proteins in a signal transduction pathway. These proteins tend to lack any intrinsic enzymatic activity themselves but instead mediate specific protein–protein interactions that drive the formation of protein complexes...
which can regulate the activity of other proteins through their ability to mediate protein-protein interactions.
This family contains three paralogous isoforms:
- ELMO1ELMO1Engulfment and cell motility protein 1 is a protein that in humans is encoded by the ELMO1 gene. ELMO1 is located on chromosome number seven in humans and is located on chromosome number thirteen in mice.- Structure :...
- ELMO2ELMO2Engulfment and cell motility protein 2 is a protein that in humans is encoded by the ELMO2 gene.-Further reading:...
- ELMO3ELMO3Engulfment and cell motility 3, also known as ELMO3, is a human gene.The protein encoded by this gene is similar to a C. elegans protein that functions in phagocytosis of apoptotic cells and in cell migration...
Structure and function
The ELMO family are evolutionarily conserved orthologsHomology (biology)
Homology forms the basis of organization for comparative biology. In 1843, Richard Owen defined homology as "the same organ in different animals under every variety of form and function". Organs as different as a bat's wing, a seal's flipper, a cat's paw and a human hand have a common underlying...
of the C. elegans
Caenorhabditis elegans
Caenorhabditis elegans is a free-living, transparent nematode , about 1 mm in length, which lives in temperate soil environments. Research into the molecular and developmental biology of C. elegans was begun in 1974 by Sydney Brenner and it has since been used extensively as a model...
protein CED-12
CED-12
CED-12 is the C. elegans ortholog of the ELMO family of mammalian adaptor proteins. It interacts with CED-5 to form a bipartite guanine nucleotide exchange factor which promotes cell migration and phagocytosis of apoptotic cells....
. All isoforms contain a series of armadillo repeats
Armadillo repeats
Armadillo repeats are named after the β-catenin-like Armadillo protein of the fruit fly Drosophila. These repeats are about 40 amino acids long and proteins that contain them have many tandemly repeated copies. Each Armadillo repeat is composed of a pair of alpha helices that form a hairpin...
, which begin at the N-terminus and extend around two thirds of the way along the protein, as well as a C-terminal proline
Proline
Proline is an α-amino acid, one of the twenty DNA-encoded amino acids. Its codons are CCU, CCC, CCA, and CCG. It is not an essential amino acid, which means that the human body can synthesize it. It is unique among the 20 protein-forming amino acids in that the α-amino group is secondary...
-rich motif and a central PH domain. They function as part of a protein complex
Protein complex
A multiprotein complex is a group of two or more associated polypeptide chains. If the different polypeptide chains contain different protein domain, the resulting multiprotein complex can have multiple catalytic functions...
with Dock180-related proteins to form a bipartite guanine nucleotide exchange factor
Guanine nucleotide exchange factor
Guanine nucleotide exchange factors activate monomeric GTPases by stimulating the release of guanosine diphosphate to allow binding of guanosine triphosphate . A variety of unrelated structural domains have been shown to exhibit guanine nucleotide exchange activity...
for Rac
RAC
-Companies:* Rent-A-Center, an American public furniture and electronics rent to own company* Royal Automobile Club, a private club in Pall Mall, London* RAC plc, a breakdown company in the United Kingdom...
(a member of the Rho family of small G proteins). The Dock180-ELMO interaction requires the ELMO PH domain and also involves binding of the ELMO proline-rich motif to the Dock180 SH3 domain
SH3 domain
The SRC Homology 3 Domain is a small protein domain of about 60 amino acids residues first identified as a conserved sequence in the viral adaptor protein v-Crk and the non-catalytic parts of enzymes such as phospholipase and several cytoplasmic tyrosine kinases such as Abl and Src...
.