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Noggin (protein)
Encyclopedia
Noggin, also known as NOG, is a protein
which in humans is encoded by the NOG gene
.
Noggin inhibits TGF-β
signal transduction by binding to TGF-β family ligands and preventing them from binding to their corresponding receptors. Noggin plays a key role in neural induction by inhibiting BMP4
, along with other TGF-β signaling inhibitors such as chordin
and follistatin
. Mouse knockout
experiments have demonstrated that noggin also plays a crucial role in bone development, joint formation, and neural tube fusion.
). By diffusing through extracellular matrices more efficiently than members of the TGF-beta superfamily, noggin may have a principal role in creating morphogenic
gradients. Noggin appears to have pleiotropic
effect, both early in development as well as in later stages. It was originally isolated from Xenopus
based on its ability to restore normal dorsal-ventral body axis in embryos that had been artificially ventralized by UV treatment. The results of the mouse knockout of noggin suggest that it is involved in numerous developmental processes, such as neural tube
fusion and joint formation. Recently, several dominant human NOG mutations in unrelated families with proximal symphalangism (SYM1) and multiple synostoses syndrome (SYNS1) were identified; both SYM1 and SYNS1 have multiple joint fusion as their principal feature, and map to the same region (17q22) as NOG. All NOG mutations altered evolutionarily conserved amino acid residues. The amino acid sequence of human noggin is highly homologous to that of Xenopus, rat and mouse.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
which in humans is encoded by the NOG gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Noggin inhibits TGF-β
TGF beta
Transforming growth factor beta is a protein that controls proliferation, cellular differentiation, and other functions in most cells. It plays a role in immunity, cancer, heart disease, diabetes, Marfan syndrome, and Loeys–Dietz syndrome....
signal transduction by binding to TGF-β family ligands and preventing them from binding to their corresponding receptors. Noggin plays a key role in neural induction by inhibiting BMP4
Bone morphogenetic protein 4
Bone morphogenetic protein 4 is a protein that in humans is encoded by` BMP4 gene.BMP4 is a member of the bone morphogenetic protein family which is part of the transforming growth factor-beta superfamily...
, along with other TGF-β signaling inhibitors such as chordin
Chordin
Chordin is a polypeptide that dorsalizes the developing embryo by binding ventralizing TGFβ proteins such as bone morphogenetic proteins. It may also play a role in organogenesis. There are five named isoforms of this protein that are produced by alternative splicing.In humans, the chordin peptide...
and follistatin
Follistatin
Follistatin also known as activin-binding protein is a protein that in humans is encoded by the FST gene. Follistatin is an autocrine glycoprotein that is expressed in nearly all tissues of higher animals....
. Mouse knockout
Knockout mouse
A knockout mouse is a genetically engineered mouse in which researchers have inactivated, or "knocked out," an existing gene by replacing it or disrupting it with an artificial piece of DNA...
experiments have demonstrated that noggin also plays a crucial role in bone development, joint formation, and neural tube fusion.
Function
The secreted polypeptide noggin, encoded by the NOG gene, binds and inactivates members of the transforming growth factor-beta (TGF-beta) superfamily signaling proteins, such as bone morphogenetic protein-4 (BMP4Bone morphogenetic protein 4
Bone morphogenetic protein 4 is a protein that in humans is encoded by` BMP4 gene.BMP4 is a member of the bone morphogenetic protein family which is part of the transforming growth factor-beta superfamily...
). By diffusing through extracellular matrices more efficiently than members of the TGF-beta superfamily, noggin may have a principal role in creating morphogenic
Morphogenesis
Morphogenesis , is the biological process that causes an organism to develop its shape...
gradients. Noggin appears to have pleiotropic
Pleiotropy
Pleiotropy occurs when one gene influences multiple phenotypic traits. Consequently, a mutation in a pleiotropic gene may have an effect on some or all traits simultaneously...
effect, both early in development as well as in later stages. It was originally isolated from Xenopus
Xenopus
Xenopus is a genus of highly aquatic frogs native to Sub-Saharan Africa. There are 19 species in the Xenopus genus...
based on its ability to restore normal dorsal-ventral body axis in embryos that had been artificially ventralized by UV treatment. The results of the mouse knockout of noggin suggest that it is involved in numerous developmental processes, such as neural tube
Neural tube
In the developing vertebrate, the neural tube is the embryo's precursor to the central nervous system, which comprises the brain and spinal cord...
fusion and joint formation. Recently, several dominant human NOG mutations in unrelated families with proximal symphalangism (SYM1) and multiple synostoses syndrome (SYNS1) were identified; both SYM1 and SYNS1 have multiple joint fusion as their principal feature, and map to the same region (17q22) as NOG. All NOG mutations altered evolutionarily conserved amino acid residues. The amino acid sequence of human noggin is highly homologous to that of Xenopus, rat and mouse.