TrkC receptor

TrkC receptor is a protein that in humans is encoded by the NTRK3 gene. It is a member of the neurotrophic tyrosine kinase receptor (NTRK) family. This kinase is a membrane-bound receptor that, upon neurotrophin binding, phosphorylates itself and members of the MAPK pathway. The presence of this kinase leads to cell differentiation and may play a role in specifying sensory neuron subtypes. Mutations in this gene have been associated with congenital insensitivity to pain with anhidrosis, self-mutilating behavior, mental retardation and cancer. TrkC receptor is also associated with the pathophysiology of depression and anxiety.

Structure

The TrkC receptor is a single-pass type I membrane protein. It contains two Ig-like C2-type (immunoglobulin-like) domains, two leucine-rich repeat domains, and one protein kinase domain. The protein kinase domain is located in the cytoplasmic region of the receptor.

Function

The TrkC receptor is part of the large family of receptor tyrosine kinases. These receptors regulate a host of cellular functions including cell growth, differentiation, and metabolism. The TrkC receptor specifically binds with high affinity to the neurotrophin NT-3. This binding leads to the phosphorylation and activation of several downstream effector proteins involved in the regulation of neuronal differentiation and survival, plasticity, and regeneration.

Clinical Significance

Mutations in the NTRK3 gene encoding the TrkC receptor have been associated with various human disorders. These include congenital insensitivity to pain with anhidrosis, a condition characterized by insensitivity to pain, inability to sweat, and intellectual disability. TrkC receptor has also been implicated in certain types of cancer. Overexpression of TrkC receptor has been observed in neuroblastomas, colorectal cancer, and other types of cancer.

See Also

• Neurotrophic tyrosine kinase receptor
• Neurotrophin
• NT-3
• Congenital insensitivity to pain with anhidrosis
• Depression
• Anxiety