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Src Homology Domain
In biology, a Src homology domain is one of the two small protein binding domains found in the Src oncoprotein. Homologs of both the Src homology 2 and Src homology 3 domains are found in numerous other proteins. The Src homology 1 domain was an early name of the protein kinase domain The protein kinase domain is a structurally conserved protein domain containing the catalytic function of protein kinases. Protein kinases are a group of enzymes that move a phosphate group onto proteins, in a process called phosphorylation. This .... In terms of initiating the cell cycle when growth factor signals are present, "Src homology domains" are found on Grb2 proteins, allowing them to bind Receptor Tyrosine Kinases (RTKs), and also on SOS proteins allowing them to interact with Grb2. This brings SOS proteins close to the membrane, where Ras-GDP is bound via a lipid "tail". SOS acts as a Guanosine exchange factor (GEF) for Ras, activating Ras to cleave a phosphate group from Raf, causing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Src (gene)
Proto-oncogene tyrosine-protein kinase Src, also known as proto-oncogene c-Src, or simply c-Src (cellular Src; pronounced "sarc", as it is short for sarcoma), is a non-receptor tyrosine kinase protein that in humans is encoded by the ''SRC'' gene. It belongs to a family of Src family kinases and is similar to the v-Src (viral Src) gene of Rous sarcoma virus. It includes an SH2 domain, an SH3 domain and a tyrosine kinase domain. Two transcript variants encoding the same protein have been found for this gene. c-Src phosphorylates specific tyrosine residues in other tyrosine kinases. It plays a role in the regulation of embryonic development and cell growth. An elevated level of activity of c-Src is suggested to be linked to cancer progression by promoting other signals. Mutations in c-Src could be involved in the malignant progression of colon cancer. c-Src should not be confused with CSK (C-terminal Src kinase), an enzyme that phosphorylates c-Src at its C-terminus and provides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oncoprotein
An oncogene is a gene that has the potential to cause cancer. In tumor cells, these genes are often mutated, or expressed at high levels.Kimball's Biology Pages. "Oncogenes" Free full text Most normal cells will undergo a programmed form of rapid cell death () when critical functions are altered and malfunctioning. Activated oncogenes can cause those cells designated for apoptosis to survive and proliferate instead. Most oncogenes began as proto-oncogenes: normal genes involved in cell growth and proliferation or inhibition of apoptosis. If, through mutation, normal genes promoting cellular growth are up-regulated (gain-of-function mutation), they will predisp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SH2 Domain
The SH2 (Src Homology 2) domain is a structurally conserved protein domain contained within the Src oncoprotein and in many other intracellular signal-transducing proteins. SH2 domains allow proteins containing those domains to dock to phosphorylated tyrosine residues on other proteins. SH2 domains are commonly found in adaptor proteins that aid in the signal transduction of receptor tyrosine kinase pathways. Background SH2 is conserved by signalization of protein tyrosine kinase, which are binding on phosphotyrosine (pTyr). In the human proteome the class of pTyr-selective recognition domains is represented by SH2 domains. The N-terminal SH2 domains of cytoplasmic tyrosine kinase was at the beginning of evolution evolved with the occurrence of tyrosine phosphorylation. At the beginning it was supposed that, these domains serve as a substrate for their target kinase. Protein-protein interactions play a major role in cellular growth and development. Modular domains, which are t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SH3 Domain
The SRC Homology 3 Domain (or SH3 domain) is a small protein domain of about 60 amino acid residues. Initially, SH3 was described as a conserved sequence in the viral adaptor protein v-Crk. This domain is also present in the molecules of phospholipase and several cytoplasmic tyrosine kinases such as Abl and Src. It has also been identified in several other protein families such as: PI3 Kinase, Ras GTPase-activating protein, CDC24 and cdc25. SH3 domains are found in proteins of signaling pathways regulating the cytoskeleton, the Ras protein, and the Src kinase and many others. The SH3 proteins interact with adaptor proteins and tyrosine kinases. Interacting with tyrosine kinases, SH3 proteins usually bind far away from the active site. Approximately 300 SH3 domains are found in proteins encoded in the human genome. In addition to that, the SH3 domain was responsible for controlling protein-protein interactions in the signal transduction pathways and regulating the interactions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Kinase Domain
The protein kinase domain is a structurally conserved protein domain containing the catalytic function of protein kinases. Protein kinases are a group of enzymes that move a phosphate group onto proteins, in a process called phosphorylation. This functions as an on/off switch for many cellular processes, including metabolism, transcription, cell cycle progression, cytoskeletal rearrangement and cell movement, apoptosis, and differentiation. They also function in embryonic development, physiological responses, and in the nervous and immune system. Abnormal phosphorylation causes many human diseases, including cancer, and drugs that affect phosphorylation can treat those diseases. Protein kinases possess a catalytic subunit which transfers the gamma phosphate from nucleoside triphosphates (almost always ATP) to the side chain of an amino acid in a protein, resulting in a conformational and/or dynamic changes affecting protein function. These enzymes fall into two broad classes, cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
