Serine/threonine-protein kinase receptor R3 is an enzyme that in humans is encoded by the ACVRL1 gene. [5] [6] [7]
ACVRL1 is a receptor in the TGF beta signaling pathway. It is also known as activin receptor-like kinase 1, or ALK1.
This gene encodes a type I cell-surface receptor for the TGF-beta superfamily of ligands. It shares with other type I receptors a high degree of similarity in serine-threonine kinase subdomains, a glycine- and serine-rich region (called the GS domain) preceding the kinase domain, and a short C-terminal tail. The encoded protein, sometimes termed ALK1, shares similar domain structures with other closely related ALK or activin receptor-like kinase proteins that form a subfamily of receptor serine/threonine kinases. Mutations in this gene are associated with hereditary hemorrhagic telangiectasia (HHT) type 2, also known as Rendu-Osler-Weber syndrome 2. [7]
Germline mutations of ACVRL1 are associated with:
Somatic mosaicism in ACVRL1 are associated with severe pulmonary arterial hypertension. [10]
ACVRL1 directly interacts with low-density lipoprotein (LDL), which implies that it might initiate the early phases of atherosclerosis. [11]
Abnormal activity of ACVRL1 has been found to be closely associated with idiopathic pulmonary arterial hypertension.
(Not to be confused with anaplastic lymphoma kinase (ALK) )
ALK4 is ACVR1B, ALK7 is ACVR1C, and ALK5 is [part of] the TGF-β type I receptor. [13]
Paracrine signaling is a form of cell signaling, a type of cellular communication in which a cell produces a signal to induce changes in nearby cells, altering the behaviour of those cells. Signaling molecules known as paracrine factors diffuse over a relatively short distance, as opposed to cell signaling by endocrine factors, hormones which travel considerably longer distances via the circulatory system; juxtacrine interactions; and autocrine signaling. Cells that produce paracrine factors secrete them into the immediate extracellular environment. Factors then travel to nearby cells in which the gradient of factor received determines the outcome. However, the exact distance that paracrine factors can travel is not certain.
Hereditary hemorrhagic telangiectasia (HHT), also known as Osler–Weber–Rendu disease and Osler–Weber–Rendu syndrome, is a rare autosomal dominant genetic disorder that leads to abnormal blood vessel formation in the skin, mucous membranes, and often in organs such as the lungs, liver, and brain.
Transforming growth factor beta (TGF-β) is a multifunctional cytokine belonging to the transforming growth factor superfamily that includes three different mammalian isoforms and many other signaling proteins. TGFB proteins are produced by all white blood cell lineages.
The transforming growth factor beta (TGFB) signaling pathway is involved in many cellular processes in both the adult organism and the developing embryo including cell growth, cell differentiation, cell migration, apoptosis, cellular homeostasis and other cellular functions. The TGFB signaling pathways are conserved. In spite of the wide range of cellular processes that the TGFβ signaling pathway regulates, the process is relatively simple. TGFβ superfamily ligands bind to a type II receptor, which recruits and phosphorylates a type I receptor. The type I receptor then phosphorylates receptor-regulated SMADs (R-SMADs) which can now bind the coSMAD SMAD4. R-SMAD/coSMAD complexes accumulate in the nucleus where they act as transcription factors and participate in the regulation of target gene expression.
Bone morphogenetic protein receptor type II or BMPR2 is a serine/threonine receptor kinase encoded by the BMPR2 gene. It binds bone morphogenetic proteins, members of the TGF beta superfamily of ligands, which are involved in paracrine signaling. BMPs are involved in a host of cellular functions including osteogenesis, cell growth and cell differentiation. Signaling in the BMP pathway begins with the binding of a BMP to the type II receptor. This causes the recruitment of a BMP type I receptor, which the type II receptor phosphorylates. The type I receptor phosphorylates an R-SMAD, a transcriptional regulator.
The bone morphogenetic protein receptor, type IA also known as BMPR1A is a protein which in humans is encoded by the BMPR1A gene. BMPR1A has also been designated as CD292.
The activin A receptor also known as ACVR1C or ALK-7 is a protein that in humans is encoded by the ACVR1C gene. ACVR1C is a type I receptor for the TGFB family of signaling molecules.
Activin receptor type-1B is a protein that in humans is encoded by the ACVR1B gene.
Activin A receptor, type I (ACVR1) is a protein which in humans is encoded by the ACVR1 gene; also known as ALK-2. ACVR1 has been linked to the 2q23-24 region of the genome. This protein is important in the bone morphogenic protein (BMP) pathway which is responsible for the development and repair of the skeletal system. While knock-out models with this gene are in progress, the ACVR1 gene has been connected to fibrodysplasia ossificans progressiva, a disease characterized by the formation of heterotopic bone throughout the body. It is a bone morphogenetic protein receptor, type 1.
Activin receptor type-2A is a protein that in humans is encoded by the ACVR2A gene. ACVR2A is an activin type 2 receptor.
(See also: List of proteins in the human body)
Endoglin (ENG) is a type I membrane glycoprotein located on cell surfaces and is part of the TGF beta receptor complex. It is also commonly referred to as CD105, END, FLJ41744, HHT1, ORW and ORW1. It has a crucial role in angiogenesis, therefore, making it an important protein for tumor growth, survival and metastasis of cancer cells to other locations in the body.
Transforming growth factor beta receptor I is a membrane-bound TGF beta receptor protein of the TGF-beta receptor family for the TGF beta superfamily of signaling ligands. TGFBR1 is its human gene.
Transforming growth factor, beta receptor II (70/80kDa) is a TGF beta receptor. TGFBR2 is its human gene.
Growth differentiation factor 2 (GDF2) also known as bone morphogenetic protein (BMP)-9 is a protein that in humans is encoded by the GDF2 gene. GDF2 belongs to the transforming growth factor beta superfamily.
Bone morphogenetic protein receptor type-1B also known as CDw293 is a protein that in humans is encoded by the BMPR1B gene.
An Activin receptor is a receptor which binds activin. These proteins are receptor-type kinases of Ser/Thr type, which have a single transmembrane domain and a specific hydrophilic Cys-rich ligand-binding domain.
Inhibin beta C chain is a protein that in humans is encoded by the INHBC gene.
Activin and inhibin are two closely related protein complexes that have almost directly opposite biological effects. Identified in 1986, activin enhances FSH biosynthesis and secretion, and participates in the regulation of the menstrual cycle. Many other functions have been found to be exerted by activin, including roles in cell proliferation, differentiation, apoptosis, metabolism, homeostasis, immune response, wound repair, and endocrine function. Conversely, inhibin downregulates FSH synthesis and inhibits FSH secretion. The existence of inhibin was hypothesized as early as 1916; however, it was not demonstrated to exist until Neena Schwartz and Cornelia Channing's work in the mid-1970s, after which both proteins were molecularly characterized ten years later.
The transforming growth factor beta (TGFβ) receptors are a family of serine/threonine kinase receptors involved in TGF beta signaling pathway. These receptors bind growth factor and cytokine signaling proteins in the TGF-beta family such as TGFβs, bone morphogenetic proteins (BMPs), growth differentiation factors (GDFs), activin and inhibin, myostatin, anti-Müllerian hormone (AMH), and NODAL.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.