Sputa nerve growth factor forms a preferable substitute to mouse 7S-β nerve growth factor

Abstract

The NGF (nerve growth factor) from Naja sputatrix has been purified by gel filtration followed by reversed-phase HPLC. The protein showed a very high ability to induce neurite formation in PC12 cells relative to the mouse NGF. Two cDNAs encoding isoforms of NGF have been cloned and an active recombinant NGF, sputa NGF, has been produced in Escherichia coli as a His-tagged fusion protein. Sputa NGF has been found to be non-toxic under both in vivo and in vitro conditions. The induction of neurite outgrowth by this NGF has been found to involve the high-affinity trkA–p75NTR complex of receptors. The pro-survival mechanism of p75NTR has been mediated by the activation of nuclear factor κB gene by a corresponding down-regulation of inhibitory κB gene. Real-time PCR and protein profiling (by surface-enhanced laser-desorption–ionization time-of-flight) have confirmed that sputa NGF up-regulates the expression of the endogenous NGF in PC12 cells. Preliminary microarray analysis has also shown that sputa NGF is capable of promoting additional beneficial effects such as the up-regulation of arginine vasopressin receptor 1A, voltage-dependent T-type calcium channel. Hence, sputa NGF forms a new and useful NGF.