TrkA Rabbit Polyclonal Antibody

Function

The Trk proto-oncogene encodes a tyrosine protein kinase, Trk A, also designated Trk gp140, that serves as a receptor for certain neurotrophic factors including nerve growth factor (NGF) and neurotrophin-3 (NT-3). Trk B is a tyrosine kinase gene highly related to Trk A. Trk B expression is confined to tissues within the central and peripheral nervous systems. The brain-derived neurotrophic factor (BDNF) and NT-3, but not NGF, can induce rapid phosphorylation on Tyrosine of Trk B gp145, one of the receptors encoded by Trk B, although BDNF elicits a response at least two orders of magnitude greater than NT-3. Thus it appears that Trk B gp145 may represent a neurotrophic receptor for BDNF and NT-3. The third member of the Trk family of tyrosine kinases, Trk C, encodes a protein designated Trk C gp145 that is preferentially expressed in brain tissue, is equally related to Trk A and Trk B and is a functional receptor for NT-3.

Background References

1. Hempstead B L et al. High-affinity NGF binding requires coexpression of the trk proto-oncogene and the low-affinity NGF receptor. Nature 350:678-683 (1991).

2. Jing S et al. Nerve growth factor mediates signal transduction through trk homodimer receptors. Neuron 9:1067-1079 (1992).

Sequence Similarity

Belongs to the protein kinase superfamily. Tyr protein kinase family. Insulin receptor subfamily.

Tissue Specificity

Isoform TrkA-I is found in most non-neuronal tissues. Isoform TrkA-II is primarily expressed in neuronal cells. TrkA-III is specifically expressed by pluripotent neural stem and neural crest progenitors.

Post-translational Modification

Ligand-mediated autophosphorylation. Interaction with SQSTM1 is phosphotyrosine-dependent. Autophosphorylation at Tyr-496 mediates interaction and phosphorylation of SHC1.; N-glycosylated. Isoform TrkA-I and isoform TrkA-II are N-glycosylated.; Ubiquitinated. Undergoes polyubiquitination upon activation; regulated by NGFR. Ubiquitination by NEDD4L leads to degradation. Ubiquitination regulates the internalization of the receptor (By similarity).

Subcellular Location

Cell membrane, Endosome, Membrane.

UNIPROT

SwissProt: P04629 Human

SwissProt: Q3UFB7 Mouse

SwissProt: P35739 Rat

Synonyms