PMID- 8161524
OWN - NLM
STAT- MEDLINE
DCOM- 19940526
LR  - 20220316
IS  - 0006-2960 (Print)
IS  - 0006-2960 (Linking)
VI  - 33
IP  - 15
DP  - 1994 Apr 19
TI  - Comparative equilibrium denaturation studies of the neurotrophins: nerve growth 
      factor, brain-derived neurotrophic factor, neurotrophin 3, and neurotrophin 4/5.
PG  - 4667-76
AB  - The neurotrophins are a family of small dimeric proteins required for the 
      development and survival of vertebrate neurons. Solvent denaturation studies were 
      used to compare recombinant human nerve growth factor (hNGF), brain-derived 
      neurotrophic factor (BDNF), neurotrophin 3 (NT-3), and neurotrophin 4/5 (NT-4/5) 
      to nerve growth factor isolated from mouse submaxillary glands (mNGF). Although 
      greater than 50% sequence identity is conserved among this family, significant 
      structural differences were revealed by the folding and unfolding of these 
      proteins. Denaturation in guanidine hydrochloride and renaturation at pH 7 and 
      3.5 were monitored by fluorescence intensity, fluorescence polarization, and 
      circular dichroism. The midpoint of equilibrium unfolding curves for all four 
      neurotrophins was independent of the technique but was dependent on protein 
      concentration, indicating that a two-state model involving native neurotrophin 
      dimers and denatured neurotrophin monomers (N2 = 2D) describes the equilibrium 
      between folded and unfolded neurotrophins. The conformational stabilities of the 
      dimeric neurotrophins revealed that mNGF had the lowest conformational stability 
      (19.3 kcal/mol); hNGF, NT-3, and NT-4/5 had intermediate stabilities, and BDNF 
      had the highest stability (26.4 kcal/mol). Recovery of native spectroscopic 
      characteristics upon removal of denaturant indicated that the unfolding process 
      is reversible. Accordingly, unfolding and refolding curves were coincident for 
      mNGF or NT-4/5 at pH 7 and 3.5 and for BDNF at pH 3.5. However, BDNF and NT-3 
      unfolding and refolding curves were not coincident at pH 7. The stability of the 
      neurotrophins decreased as pH decreased, with compact monomeric intermediates (N2 
      = [2I] = 2D) becoming populated below pH 4. The differences in stability, pH 
      dependence, and coincidence of refolding curves distinguish the homologous 
      structures of the neurotrophins.
FAU - Timm, D E
AU  - Timm DE
AD  - Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 
      44106.
FAU - de Haseth, P L
AU  - de Haseth PL
FAU - Neet, K E
AU  - Neet KE
LA  - eng
GR  - GM08056/GM/NIGMS NIH HHS/United States
GR  - NS24380/NS/NINDS NIH HHS/United States
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Biochemistry
JT  - Biochemistry
JID - 0370623
RN  - 0 (Brain-Derived Neurotrophic Factor)
RN  - 0 (Macromolecular Substances)
RN  - 0 (Nerve Growth Factors)
RN  - 0 (Nerve Tissue Proteins)
RN  - 0 (Neurotrophin 3)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Solvents)
RN  - 0 (brain-derived growth factor)
RN  - 145172-44-7 (neurotrophin 5)
RN  - P658DCA9XD (neurotrophin 4)
SB  - IM
MH  - Animals
MH  - *Brain-Derived Neurotrophic Factor
MH  - Circular Dichroism
MH  - Drug Stability
MH  - Fluorescence Polarization
MH  - Humans
MH  - Hydrogen-Ion Concentration
MH  - Macromolecular Substances
MH  - Mice
MH  - Nerve Growth Factors/*chemistry
MH  - Nerve Tissue Proteins/*chemistry
MH  - Neurotrophin 3
MH  - Protein Conformation
MH  - Protein Denaturation
MH  - Recombinant Proteins/chemistry
MH  - Solvents
MH  - Spectrometry, Fluorescence
EDAT- 1994/04/19 00:00
MHDA- 1994/04/19 00:01
CRDT- 1994/04/19 00:00
PHST- 1994/04/19 00:00 [pubmed]
PHST- 1994/04/19 00:01 [medline]
PHST- 1994/04/19 00:00 [entrez]
AID - 10.1021/bi00181a602 [doi]
PST - ppublish
SO  - Biochemistry. 1994 Apr 19;33(15):4667-76. doi: 10.1021/bi00181a602.