title: The unprocessed C-terminal dipeptide of recombinant beta-nerve growth factor determines three stable forms with distinct biological activities.
abstract: The processing of polypeptide neurotrophins in the nervous system is poorly understood. In this paper, we provide information on the effects of C-terminal processing of nerve growth factor. Three forms of recombinant mouse beta-nerve growth factor (rNGF) were produced and isolated from insect cells infected with a recombinant baculovirus. The three purified forms of rNGF exhibited distinct biological activities and differed in their abilities to compete with high affinity binding of mouse beta-nerve growth factor (mNGF). However, they were chemically and structurally indistinguishable from each other. All three forms of rNGF differed from mature mNGF from mouse submaxillary gland in that the C-terminal Arg-Gly dipeptide had not been proteolytically removed. Removal of the C-terminal dipeptide by gamma-NGF peptidase treatment converted the three forms into a single form identical with mature mNGF. The above results demonstrate that a single polypeptide of rNGF, due to the presence of a C-terminal dipeptide, exhibits three stable dimeric protein conformations with distinct biological activities. The apparent lack of gamma-NGF peptidase in the nervous system raises the possibility that the biologically significant form of NGF may differ from mature mNGF; such a difference may be of physiological relevance.
authors.affiliation: Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106.
authors.forename: Y
authors.initials: Y
authors.lastname: Luo
authors.forename: K E
authors.initials: KE
authors.lastname: Neet
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D001667:Binding, Competitive; D015153:Blotting, Western; D002460:Cell Line; D002846:Chromatography, Affinity; D002942:Circular Dichroism; D004151:Dipeptides / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005814:Genes, Viral; D007525:Isoelectric Focusing; D008297:Male; D051379:Mice; D009414:Nerve Growth Factors / Q000235:genetics* / Q000378:metabolism; D016716:PC12 Cells; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D004151:Dipeptides; D009414:Nerve Growth Factors; D011994:Recombinant Proteins