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IGFBP
The insulin-like growth factor-binding protein (IGFBP) serves as a transport protein for insulin-like growth factor 1 (IGF-1). Function Approximately 98% of IGF-1 is always bound to one of six binding proteins (IGF-BP). IGFBP-3, the most abundant protein, accounts for 80% of all IGF binding. IGF-1 binds to IGFBP-3 in a 1:1 molar ratio. IGF-BP also binds to IGF-1 inside the liver, allowing growth hormone to continuously act upon the liver to produce more IGF-1. IGF binding proteins (IGFBPs) are proteins of 24 to 45 kDa. All six IGFBPs share 50% homology with each other and have binding affinities for IGF-I and IGF-II at the same order of magnitude as the ligands have for the IGF-IR. The IGFBPs help to lengthen the half-life of circulating IGFs in all tissues, including the prostate. Individual IGFBPs may act to enhance or attenuate IGF signaling depending on their physiological context (i.e. cell type). Even with these similarities, some characteristics are different: chromoso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IGFBP3
Insulin-like growth factor-binding protein 3, also known as IGFBP-3, is a protein that in humans is encoded by the ''IGFBP3'' gene. IGFBP-3 is one of six insulin-like growth factor-binding protein, IGF binding proteins (IGFBP1, IGFBP-1 to IGFBP6, IGFBP-6) that have highly conserved structures and bind the insulin-like growth factors IGF-1 and IGF-2 with high affinity. IGFBP7, IGFBP-7, sometimes included in this family, shares neither the conserved structural features nor the high IGF affinity. Instead, IGFBP7, IGFBP-7 binds IGF1R, which blocks IGF-1 and IGF-2 binding, resulting in apoptosis. Function IGFBP-3 was first isolated, characterized, and quantitated in human plasma, in 1986. It has well-documented functions in the circulation, in the extracellular environment, and inside cells. It is the main IGF transport protein in the bloodstream, where it carries the growth factors predominantly in stable complexes that contain the binding protein, either IGF-1 or IGF-2, and a third ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IGFBP7
Insulin-like growth factor-binding protein 7 is a protein that in humans is encoded by the ''IGFBP7'' gene. The major function of the protein is the regulation of availability of insulin-like growth factors (IGFs) in tissue as well as in modulating IGF binding to its receptors. IGFBP7 binds to IGF with low affinity compared to IGFBPs 1-6. It also stimulates cell adhesion. The protein is implicated in some cancers. Structure The edited sites are found within the insulin growth factor binding domain of IGFBP7 and also Heparin binding domain. This region is also a site for proteolytic cleavage. Structural analysis of the edited sites determined that the two amino acids that corresponded to the edited sites are not directly involved in binding to IGF-1 but are found in regions flanking them. At position 78 in unedited version of the transcript there is an Arginine close to residue valine-49. This Valine is important in hydrophobic interaction of Phenylalanine of IGF-1. A substitut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IGFBP6
Insulin-like growth factor-binding protein 6 (IGFBP-6) is a protein that in humans is encoded by the ''IGFBP6'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei .... References Further reading * * * * * * * * * * * * * * * * * * {{gene-12-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IGFBP2
Insulin-like growth factor-binding protein 2 is a protein that in humans is encoded by the ''IGFBP2'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei .... References Further reading * * * * * * * * * * * * * * * * * * {{gene-2-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IGFBP4
Insulin-like growth factor-binding protein 4 is a protein that in humans is encoded by the ''IGFBP4'' gene. Function This gene is a member of the insulin-like growth factor binding protein (IGFBP) family and encodes a protein with an IGFBP domain and a thyroglobulin type-I domain. The protein binds both insulin-like growth factors (IGFs) I and II and circulates in the plasma in both glycosylated and non-glycosylated forms. Binding of this protein prolongs the half-life of the IGFs and alters their interaction with cell surface receptors. IGFBP-4 is a unique protein and it consistently inhibits several cancer cells in vivo and in vitro. Its inhibitory action has been shown in vivo in prostate and colon. It is secreted by all colon cancer cells. Clinical significance The protein itself does not prevent the formation of cancer. However it may reduce the growth of cancer and act as an apoptotic factor. Interactions IGFBP4 has been shown to interact with Insulin-like growth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IGFBP5
Insulin-like growth factor-binding protein 5 (IBF-5) is a protein that in humans is encoded by the ''IGFBP5'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei .... An IGFBP5 gene was recently identified as being important for adaptation to varying water salinity in fish. References Further reading * * * * * * * * * * * * * * * * * * {{gene-2-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insulin-like Growth Factor 1
Insulin-like growth factor 1 (IGF-1), also called somatomedin C, is a hormone similar in tertiary structure, molecular structure to insulin which plays an important role in childhood growth, and has Anabolism, anabolic effects in adults. In the 1950s IGF-1 was called "sulfation factor" because it stimulated sulfation of cartilage in vitro, and in the 1970s due to its effects it was termed "nonsuppressible insulin-like activity" (NSILA). IGF-1 is a protein that in humans is Genetic code, encoded by the ''IGF1'' gene. IGF-1 consists of 70 amino acids in a single chain with three intramolecular reaction, intramolecular disulfide bridges. IGF-1 has a molecular weight of 7,649 Dalton (unit), daltons. In dogs, an ancient mutation in IGF1 is the primary cause of the Toy dog, toy phenotype. IGF-1 is produced primarily by the liver. Production is stimulated by growth hormone (GH). Most of IGF-1 is bound to one of 6 binding proteins (IGF-BP). IGFBP-1 is regulated by insulin. IGF-1 is pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IGFBP1
Insulin-like growth factor-binding protein 1 (IBP-1) also known as placental protein 12 (PP12) is a protein that in humans is encoded by the ''IGFBP1'' gene. Function This gene is a member of the Insulin-like growth factor-binding protein (IGFBP) family and encodes a protein with an IGFBP domain and a type-I thyroglobulin domain. The protein binds both insulin-like growth factor The insulin-like growth factors (IGFs) are proteins with high sequence similarity to insulin. IGFs are part of a complex system that cells use to communicate with their physiologic environment. This complex system (often referred to as the IGF ...s (IGFs) I and II and circulates in the plasma. Binding of this protein prolongs the half-life of the IGFs and alters their interaction with cell surface receptors. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. References Further reading * * * * * * * * * * * * * * * * * * * {{gene-7-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transport Protein
A transport protein (variously referred to as a transmembrane pump, transporter, escort protein, acid transport protein, cation transport protein, or anion transport protein) is a protein that serves the function of moving other materials within an organism. Transport proteins are vital to the growth and life of all living things. There are several different kinds of transport proteins. Carrier proteins are proteins involved in the movement of ions, small molecules, or macromolecules, such as another protein, across a biological membrane. Carrier proteins are integral membrane proteins; that is, they exist within and span the membrane across which they transport substances. The proteins may assist in the movement of substances by facilitated diffusion (i.e., passive transport) or active transport. These mechanisms of movement are known as carrier-mediated transport. Each carrier protein is designed to recognize only one substance or one group of very similar substances. Resea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insulin-like Growth Factor Receptor
The insulin-like growth factor receptors (IGFRs) include the following two receptors: * Insulin-like growth factor 1 receptor (IGF-1R) * Insulin-like growth factor 2 receptor (IGF-2R) See also * Insulin-like growth factor * Insulin-like growth factor 1 * Insulin-like growth factor 2 * Insulin-like growth factor-binding protein The insulin-like growth factor-binding protein (IGFBP) serves as a transport protein for insulin-like growth factor 1 (IGF-1). Function Approximately 98% of IGF-1 is always bound to one of six binding proteins (IGF-BP). IGFBP-3, the most abun ... References G protein-coupled receptors {{transmembranereceptor-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Domains
In molecular biology, a protein domain is a region of a protein's polypeptide chain that is self-stabilizing and that folds independently from the rest. Each domain forms a compact folded three-dimensional structure. Many proteins consist of several domains, and a domain may appear in a variety of different proteins. Molecular evolution uses domains as building blocks and these may be recombined in different arrangements to create proteins with different functions. In general, domains vary in length from between about 50 amino acids up to 250 amino acids in length. The shortest domains, such as zinc fingers, are stabilized by metal ions or disulfide bridges. Domains often form functional units, such as the calcium-binding EF hand domain of calmodulin. Because they are independently stable, domains can be "swapped" by genetic engineering between one protein and another to make chimeric proteins. Background The concept of the domain was first proposed in 1973 by Wetlaufer after ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
