TY - JOUR
T1 - Multiple functions of precursor BDNF to CNS neurons
T2 - Negative regulation of neurite growth, spine formation and cell survival
AU - Koshimizu, Hisatsugu
AU - Kiyosue, Kazuyuki
AU - Hara, Tomoko
AU - Hazama, Shunsuke
AU - Suzuki, Shingo
AU - Uegaki, Koichi
AU - Nagappan, Guhan
AU - Zaitsev, Eugene
AU - Hirokawa, Takatsugu
AU - Tatsu, Yoshiro
AU - Ogura, Akihiko
AU - Lu, Bai
AU - Kojima, Masami
N1 - Funding Information:
We thank Dr. N.X. Cawley (NICHD, NIH) for critical reading of this manuscript. We thank Dr. H. Nawa (Brain Research Institute, Niigata University) for Sindbis vector (IRES-GFP vector). We thank Dr. S. Koizumi (Novartis Pharma K.K.) for proNGF plasmid. We thank Dr. T. Watanabe (Department of Urology, Asahikawa Medical College) for anti-SgII antibody. We thank Drs. B. Hempstead and K. Teng (Weill Medical College of Cornell University) for proNT-3 vector. We thank Drs. N. Takei (Brain Research Institute, Niigata University) for helpful discussion. We thank M. Kashihara and M. Ohtsuka (RICE, AIST) for technical assistance. This work was supported by Grant-in-Aid for Scientific Research on Priority Areas-Elucidation of neural network function in the brain-from the Ministry of Education, Culture, Sports, Science and Technology of Japan (40344171) (MK), Japan Society for the Promotion of Science (JSPS) (HK), Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST) (MK), and The National Institute of Mental Health (NIMH) and NICHD intramural research programs (BL). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
PY - 2009
Y1 - 2009
N2 - Background. Proneurotrophins and mature neurotrophins elicit opposite effects via the p75 neurotrophin receptor (p75NTR) and Trk tyrosine kinase receptors, respectively; however the molecular roles of proneurotrophins in the CNS are not fully understood. Results. Based on two rare single nucleotide polymorphisms (SNPs) of the human brain-derived neurotrophic factor (BDNF) gene, we generated R125M-, R127L- and R125M/R127L-BDNF, which have amino acid substitution(s) near the cleavage site between the pro- and mature-domain of BDNF. Western blot analyses demonstrated that these BDNF variants are poorly cleaved and result in the predominant secretion of proBDNF. Using these cleavage-resistant proBDNF (CR-proBDNF) variants, the molecular and cellular roles of proBDNF on the CNS neurons were examined. First, CR-proBDNF showed normal intracellular distribution and secretion in cultured hippocampal neurons, suggesting that inhibition of proBDNF cleavage does not affect intracellular transportation and secretion of BDNF. Second, we purified recombinant CR-proBDNF and tested its biological effects using cultured CNS neurons. Treatment with CR-proBDNF elicited apoptosis of cultured cerebellar granule neurons (CGNs), while treatment with mature BDNF (matBDNF) promoted cell survival. Third, we examined the effects of CR-proBDNF on neuronal morphology using more than 2-week cultures of basal forebrain cholinergic neurons (BFCNs) and hippocampal neurons. Interestingly, in marked contrast to the action of matBDNF, which increased the number of cholinergic fibers and hippocampal dendritic spines, CR-proBDNF dramatically reduced the number of cholinergic fibers and hippocampal dendritic spines, without affecting the survival of these neurons. Conclusion. These results suggest that proBDNF has distinct functions in different populations of CNS neurons and might be responsible for specific physiological cellular processes in the brain.
AB - Background. Proneurotrophins and mature neurotrophins elicit opposite effects via the p75 neurotrophin receptor (p75NTR) and Trk tyrosine kinase receptors, respectively; however the molecular roles of proneurotrophins in the CNS are not fully understood. Results. Based on two rare single nucleotide polymorphisms (SNPs) of the human brain-derived neurotrophic factor (BDNF) gene, we generated R125M-, R127L- and R125M/R127L-BDNF, which have amino acid substitution(s) near the cleavage site between the pro- and mature-domain of BDNF. Western blot analyses demonstrated that these BDNF variants are poorly cleaved and result in the predominant secretion of proBDNF. Using these cleavage-resistant proBDNF (CR-proBDNF) variants, the molecular and cellular roles of proBDNF on the CNS neurons were examined. First, CR-proBDNF showed normal intracellular distribution and secretion in cultured hippocampal neurons, suggesting that inhibition of proBDNF cleavage does not affect intracellular transportation and secretion of BDNF. Second, we purified recombinant CR-proBDNF and tested its biological effects using cultured CNS neurons. Treatment with CR-proBDNF elicited apoptosis of cultured cerebellar granule neurons (CGNs), while treatment with mature BDNF (matBDNF) promoted cell survival. Third, we examined the effects of CR-proBDNF on neuronal morphology using more than 2-week cultures of basal forebrain cholinergic neurons (BFCNs) and hippocampal neurons. Interestingly, in marked contrast to the action of matBDNF, which increased the number of cholinergic fibers and hippocampal dendritic spines, CR-proBDNF dramatically reduced the number of cholinergic fibers and hippocampal dendritic spines, without affecting the survival of these neurons. Conclusion. These results suggest that proBDNF has distinct functions in different populations of CNS neurons and might be responsible for specific physiological cellular processes in the brain.
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U2 - 10.1186/1756-6606-2-27
DO - 10.1186/1756-6606-2-27
M3 - Article
C2 - 19674479
AN - SCOPUS:70349241688
SN - 1756-6606
VL - 2
JO - Molecular brain
JF - Molecular brain
IS - 1
M1 - 27
ER -