Title: Neurotrophins
Literature References: Family of highly conserved, target-derived, secretory proteins that promote the differentiation, growth, and survival of neurons in the peripheral and central nervous systems. Produced in limiting amounts by innervated tissues to enhance neuronal differentiation and survival. Five closely related factors have been identified: nerve growth factor (NGF),
q.v., brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), NT-4, and NT-5. Neurotrophins differ in their sites of synthesis, developmental patterns of expression, and neuronal targets. Amino acid sequences are highly homologous. Most of the sequence differences are contained in 4 specific regions which are presumed to be responsible for the biological specificities of the factors. Purification of BDNF from pig brain: Y.-A. Barde
et al., EMBO J. 1, 549 (1982). Cloning and expression of BDNF: J. Leibrock
et al., Nature 341, 149 (1989). Identification of rat NT-3: P. C. Maisonpierre
et al., Science 247, 1446 (1990); of human NT-3: Y. Kaisho
et al., FEBS Lett. 266, 187 (1990); A. Rosenthal
et al., Neuron 4, 767 (1990). Isolation of NT-4 from
Xenopus laevis: F. Hallb??k
et al., ibid. 6, 845 (1991). Identification of NT-5 in rat and human: L. R. Berkemeier
et al., ibid. 7, 857 (1991). Proposed identity of NT-5 as the mammalian homolog of Xenopus NT-4: N. Y. Ip
et al., Proc. Natl. Acad. Sci. USA 89, 3060 (1992). Comparison of neurotrophins and other neurotrophic factors: H. Thoenen,
Trends Neurosci. 14, 165 (1991). Discussion of neurotrophin receptors: S. O. Meakin, E. M. Shooter,
ibid. 15, 323 (1992). Review of amino acid sequences and molecular structure: T. Ebendal,
J. Neurosci. Res. 32, 461-470 (1992). Review of bioactivity and distribution in the nervous system: G. Vantini,
Psychoneuroendocrinology 17, 401-410 (1992); of bioactivity and therapeutic potential in neurologic disease: F. F. Eide
et al., Exp. Neurol. 121, 200-214 (1993).
Derivative Type: Brain-derived neurotrophic factor
Synonyms: BDNF
Properties: 119 Amino acid peptide; mol wt ~13.5 kDa. pI ~9.99. Localized primarily, but not exclusively, in CNS. Amino acid sequence identical in human, pig, mouse and rat. Exhibits ~50% sequence homology with NGF.
Derivative Type: Neurotrophin-3
CAS Registry Number: 130939-66-1
Synonyms: NT-3; HDNF; hippocampal-derived neurotrophic factor; nerve growth factor-2; NGF-2; neuronotrophin-3
Properties: 119 Amino acid peptide; mol wt ~13.5 kDa. pI ~9.5. Produced primarily in peripheral tissues; also produced in the CNS. Amino acid sequence identical in human, mouse and rat. Exhibits ~57% sequence homology with NGF; ~58% homology with BDNF.
