Search results
Results from the WOW.Com Content Network
The receptors are generally activated by dimerization and substrate presentation. Receptor tyrosine kinases are part of the larger family of protein tyrosine kinases, encompassing the receptor tyrosine kinase proteins which contain a transmembrane domain, as well as the non-receptor tyrosine kinases which do not possess transmembrane domains. [4]
Cell membrane receptors can be further classified into ion channel linked receptors, G-Protein coupled receptors and enzyme linked receptors. Ion channels receptors are large transmembrane proteins with a ligand activated gate function. When these receptors are activated, they may allow or block passage of specific ions across the cell membrane.
The signaling molecule binds to the receptor on the outside of the cell and causes a conformational change on the catalytic function located on the receptor inside the cell. Examples of the enzymatic activity include: Receptor tyrosine kinase, as in fibroblast growth factor receptor. Most enzyme-linked receptors are of this type. [3]
Enzyme-linked receptors are either enzymes themselves, or directly activate associated enzymes. These are typically single-pass transmembrane receptors, with the enzymatic component of the receptor kept intracellular. The majority of enzyme-linked receptors are, or associate with, protein kinases. G protein-coupled receptors are integral ...
G protein-coupled receptor kinases (GPCRKs, GRKs) are a family of protein kinases within the AGC (protein kinase A, protein kinase G, protein kinase C) group of kinases. Like all AGC kinases, GRKs use ATP to add phosphate to Serine and Threonine residues in specific locations of target proteins.
Some tyrosine receptor kinases (e.g., the platelet-derived growth factor receptor) can form heterodimers with other similar but not identical kinases of the same subfamily, allowing a highly varied response to the extracellular signal. Trans-autophosphorylation (phosphorylation by the other kinase in the dimer) of the kinase.
In order to become phosphorylated, the inhibitory receptor has to be brought in close proximity to the kinase. This may be achieved by co-crosslinking with an ITAM motif of activating receptor that recruits a Src family kinase. ITIMs place phosphatases near ITAM-containing receptors, allowing phosphatases to dephosphorylate.
Tropomyosin receptor kinase A (TrkA), [5] also known as high affinity nerve growth factor receptor, neurotrophic tyrosine kinase receptor type 1, or TRK1-transforming tyrosine kinase protein is a protein that in humans is encoded by the NTRK1 gene. [6] This gene encodes a member of the neurotrophic tyrosine kinase receptor (NTKR) family.