Bone morphogenetic protein

The bone morphogenetic proteins (english bone morphogenetic proteins, BMPs ) are a group similar to each other signaling proteins that are secreted by animal cells to affect neighboring cells, called cytokines. BMPs are a component of the TGF- β signaling pathway, one of the fundamental signal systems for the communication between cells. The BMPs are also known as paracrine signaling molecules.

The BMPs and the associated TGF- β signaling pathway are found in such diverse organisms such as humans, the fruit fly (Drosophila), zebrafish or the nematode Caenorhabditis elegans and many other multicellular organisms studied to date in a comparable form. Only the name varies and is called in Drosophila Decapentaplegic ( Dpp ). The TGF- β signaling pathway plays an important role in many stages of development, with all of these organisms. Thus, this signaling pathway, for example, in the early development of the fruit fly embryo controls the division of the body into the abdominal and back half.

The genes encoding for BMPs in humans are: BMP1 ( bone morphogenetic protein 1), BMP2, BMP3, BMP4, BMP5, BMP6, BMP7, BMP8A, BMP8B, BMP10, BMP15, GDF10

Operation

The BMPs are secreted by the signaling cell and diffuse to neighboring cells. There they bind to membrane receptors, which pass forward this signal through the cell membrane into the cell interior. In a signaling cascade inside the cell, this message is finally transmitted from other proteins in the cell nucleus. This signal can then (depending on the development context) lead to a change in the nucleus of gene activity - which ultimately leads to the fact that the recipient cell their protein composition, which changes their properties.

The type of the BMP, the strength and duration of the signal as well as the condition of the recipient cell in the reception of the signal determine the response of the recipient cell to said signal. This complicates a simplistic description of the BMPs function. The TGF- β signaling system is used again and again in the course of development of an organism for communication between cell assemblies, to control developmental events in diverse ways and to regulate. The name derives from the BMPs in this respect was their ability to stimulate the growth factors bone formation in vertebrates, but not their only function.

The distributed BMPs can be intercepted by other proteins such as chordin and noggin from Spemann organizer and rendered inactive, whereby an attenuation or deactivation of the signal is achieved. Chordin, inter alia, inhibit the effects of BMP4 on the blastopore, which influence a gradient that leads to gastrulation.

BMPs not only affect the bone formation. At the Frog and in humans they cause of apoptosis ( programmed cell death ) for the regression of webbed and thus the formation of the fingers.