In vitro receptor binding properties of a "painless" NGF mutein, linked to hereditary sensory autonomic neuropathy type V.
Nerve Growth Factor (NGF) signalling is mediated by the TrkA and p75NTR receptors. Besides its neurotrophic and survival activities, NGF displays a potent pro-nociceptive activity. Recently, a missense point mutation was found in the NGFB gene (C661T, leading to the aminoacid substitution R100W) of individuals affected by a form of hereditary loss of pain perception (hereditary sensory and autonomic neuropathy type V, HSAN V). In order to gain insights into the functional consequences of the HSAN V NGF mutation, two sets of hNGFR100 mutants were expressed in Escherichia coli and purified, as mature NGF or proNGF, for in vitro receptor binding studies. Here, we show by Surface Plasmon Resonance analysis that the R100 mutation selectively disrupts binding of hNGF to p75NTR receptor, to an extent which depends on the substituting residue at position 100, while the affinity of hNGFR100 mutants for TrkA receptor is not affected. As for unprocessed hproNGF, the binding of the R100 variants to p75NTR receptor shows only a limited impairment, showing that the impact of the R100 mutation on p75NTR receptor binding is greater in the context of mature, processed hNGF. These results provide a basis for elucidating the mechanisms underlying the clinical manifestations of HSAN V patients, and provide a basis for the development of "painless" hNGF molecules with therapeutic potential.
Covaceuszach
Sonia
S
Lay Line Genomics S.p.A., Via Prospero Colonna 32, 00149 Rome, Italy.
Capsoni
Simona
S
Marinelli
Sara
S
Pavone
Flaminia
F
Ceci
Marcello
M
Ugolini
Gabriele
G
Vignone
Domenico
D
Amato
Gianluca
G
Paoletti
Francesca
F
Lamba
Doriano
D
Cattaneo
Antonino
A
D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D009477:Hereditary Sensory and Autonomic Neuropathies / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009154:Mutation; D020932:Nerve Growth Factor / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D000699:Pain Insensitivity, Congenital / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D020917:Receptor, trkA / Q000378:metabolism*; D017475:Receptors, Nerve Growth Factor / Q000378:metabolism*; D020349:Surface Plasmon Resonance
C502240:NGF protein, human; C484065:NGFR protein, human; D009419:Nerve Tissue Proteins; D017475:Receptors, Nerve Growth Factor; D020932:Nerve Growth Factor; D020917:Receptor, trkA