1. Academic Validation
  2. Bone morphogenetic protein-5 (BMP-5) promotes dendritic growth in cultured sympathetic neurons

Bone morphogenetic protein-5 (BMP-5) promotes dendritic growth in cultured sympathetic neurons

  • BMC Neurosci. 2001;2:12. doi: 10.1186/1471-2202-2-12.
H N Beck 1 K Drahushuk D B Jacoby D Higgins P J Lein
Affiliations

Affiliation

  • 1 Division of Toxicology, Dept of Environmental Health Sciences, Johns Hopkins University, Baltimore, MD, USA. hbeck@jhsph.edu
Abstract

Background: BMP-5 is expressed in the nervous system throughout development and into adulthood. However its effects on neural tissues are not well defined. BMP-5 is a member of the 60A subgroup of BMPs, other members of which have been shown to stimulate dendritic growth in central and peripheral neurons. We therefore examined the possibility that BMP-5 similarly enhances dendritic growth in cultured sympathetic neurons.

Results: Sympathetic neurons cultured in the absence of serum or glial cells do not form dendrites; however, addition of BMP-5 causes these neurons to extend multiple dendritic processes, which is preceded by an increase in phosphorylation of the Smad-1 transcription factor. The dendrite-promoting activity of BMP-5 is significantly inhibited by the BMP antagonists noggin and Follistatin and by a BMPR-IA-Fc chimeric protein. RT-PCR and immunocytochemical analyses indicate that BMP-5 mRNA and protein are expressed in the superior cervical ganglia (SCG) during times of initial growth and rapid expansion of the dendritic arbor.

Conclusions: These data suggest a role for BMP-5 in regulating dendritic growth in sympathetic neurons. The signaling pathway that mediates the dendrite-promoting activity of BMP-5 may involve binding to BMPR-IA and activation of Smad-1, and relative levels of BMP antagonists such as noggin and Follistatin may modulate BMP-5 signaling. Since BMP-5 is expressed at relatively high levels not only in the developing but also the adult nervous system, these findings suggest the possibility that BMP-5 regulates dendritic morphology not only in the developing, but also the adult nervous system.

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