TY - JOUR T1 - A Novel p75 Neurotrophin Receptor-Related Protein, NRH2, Regulates Nerve Growth Factor Binding to the TrkA Receptor JF - The Journal of Neuroscience JO - J. Neurosci. SP - 2742 LP - 2749 DO - 10.1523/JNEUROSCI.3960-03.2004 VL - 24 IS - 11 AU - Simon S. Murray AU - Pilar Perez AU - Ramee Lee AU - Barbara L. Hempstead AU - Moses V. Chao Y1 - 2004/03/17 UR - http://www.jneurosci.org/content/24/11/2742.abstract N2 - Nerve growth factor (NGF) functions as a ligand for two receptors, the TrkA tyrosine kinase receptor and the p75 neurotrophin receptor (p75NTR). The Ig-like domains of Trk receptors and the cysteine-rich repeats of p75NTR are involved in binding to the neurotrophins. Recently, a closely related gene to p75NTR called neurotrophin receptor homolog-2 (NRH2) was identified; however, the function of NRH2 and its relevance to neurotrophin signaling are unclear. NRH2 contains a similar transmembrane and intracellular domain as p75NTR but lacks the characteristic cysteine-rich repeats in the extracellular domain. Here we show that NRH2 is expressed in several neuronal populations that also express p75NTR and Trk receptors. NRH2 does not bind to NGF; however, coimmunoprecipitation experiments demonstrate that NRH2 is capable of interacting with TrkA receptors. Coexpression of NRH2 with TrkA receptors resulted in the formation of high-affinity binding sites for NGF. These results indicate that a transmembrane protein related to p75NTR is capable of modulating Trk receptor binding properties. ER -