Bone morphogenetic protein 4
Encyclopedia
Bone morphogenetic protein 4 is a protein
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...

 that in humans is encoded by` BMP4 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...

.

BMP4 is a member of the bone morphogenetic protein family which is part of the transforming growth factor-beta superfamily. The superfamily includes large families of growth and differentiation factors.

History

Bone morphogenetic proteins were originally identified by an ability of demineralized bone extract to induce endochondral osteogenesis in vivo in an extraskeletal site.

Function

This particular family member plays an important role in the onset of endochondral bone formation in humans. It has been shown to be involved in muscle development, bone mineralization, and uteric bud development.

In human embryonic development, BMP4 is a critical signaling molecule required for the early differentiation of the embryo and establishing of a dorsal-ventral axis. BMP4 is secreted from the dorsal portion of the notochord
Notochord
The notochord is a flexible, rod-shaped body found in embryos of all chordates. It is composed of cells derived from the mesoderm and defines the primitive axis of the embryo. In some chordates, it persists throughout life as the main axial support of the body, while in most vertebrates it becomes...

, and it acts in concert with sonic hedgehog
Sonic hedgehog
Sonic hedgehog homolog is one of three proteins in the mammalian signaling pathway family called hedgehog, the others being desert hedgehog and Indian hedgehog . SHH is the best studied ligand of the hedgehog signaling pathway. It plays a key role in regulating vertebrate organogenesis, such as...

 (released from the ventral portion of the notochord) to establish a dorsal-ventral axis for the differentiation of later structures.

BMP4 stimulates differentiation of overlying ectodermal tissue.

Inhibition

Inhibition of the BMP4 signal (by 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...

, noggin, or 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....

) causes the ectoderm to differentiate into the neural plate
Neural plate
In human embryology, formation of neural plate is the first step of neurulation. It is created by a flat thickening opposite to the primitive streak of the ectoderm.-Development:...

. If these cells also receive signals from FGF
FGF
FGF may refer to:* Federación Gallega de Fútbol, the governing body of the sport of football in Galicia, Spain* Fédération Guinéenne de Football, the governing body of football in Guinea...

, they will differentiate into the spinal cord; in the absence of FGF
FGF
FGF may refer to:* Federación Gallega de Fútbol, the governing body of the sport of football in Galicia, Spain* Fédération Guinéenne de Football, the governing body of football in Guinea...

 the cells become brain tissue.

Configurations

Alternative splicing in the 5' untranslated region of this gene has been described and three variants are described, all encoding an identical protein.

BMP4 is a polypeptide belonging to the TGF-β superfamily of proteins. It, like other bone morphogenetic proteins, is involved in bone and cartilage development, specifically tooth and limb development and fracture repair.

Disease

BMP4 has also been implicated in Fibrodysplasia Ossificans Progressiva
Fibrodysplasia ossificans progressiva
Fibrodysplasia ossificans progressiva , sometimes referred to as Stone Man Syndrome, is an extremely rare disease of the connective tissue. A mutation of the body's repair mechanism causes fibrous tissue to be ossified when damaged. In many cases, injuries can cause joints to become permanently...

 in which it is overexpressed. Increase in expression of BMP4 has been associated with a variety of bone diseases, including the heritable disorder Fibrodysplasia Ossificans Progressiva
Fibrodysplasia ossificans progressiva
Fibrodysplasia ossificans progressiva , sometimes referred to as Stone Man Syndrome, is an extremely rare disease of the connective tissue. A mutation of the body's repair mechanism causes fibrous tissue to be ossified when damaged. In many cases, injuries can cause joints to become permanently...

.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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