Expression and polarization of VGF in developing hippocampal neurons

doi:10.1016/0165-3806(96)00108-3

Developmental Brain Research

Volume 96, Issues 1–2, 23 October 1996, Pages 219-228

https://doi.org/10.1016/0165-3806(96)00108-3 Get rights and content

Abstract

VGF is an NGF-inducible protein whose expression closely correlates with PC12 cell neurite outgrowth. Immunolocalization of VGF in PC12 cells by electron microscopy revealed labeling of a subpopulation of large dense core vesicles. To determine whether VGF expression may be involved in neural and axonal differentiation, we examined VGF immunoreactivity in developing cultured hippocampal neurons. Most VGF appeared to be in vesicles which were present in neurons from the earliest developmental stages and were particularly abundant in a small number of neurons, most of which were GABAergic. VGF became restricted to axons after dendrites had begun to mature, a stage more closely associated with synaptogenesis than axonal polarization. Colocalization studies suggest that VGF-containing and synaptophysin-containing vesicles are distinct and differentially distributed.

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First, we noted in our confocal studies that endogenous VGF and VGF:GFP fusion proteins (e.g. VGF-(1-65):GFP:VGF-(545-617)) only partially colocalize in LDCV-like particles. Although one explanation for this may be that these VGF:GFP proteins are not targeted exclusively to LDCVs, previous EM studies indicated that endogenous VGF was not found in all PC12 cell LDCVs but rather only in a subset (8), and gradient fractionation suggests that vesicles containing VGF and/or VGF-(1-65):GFP:VGF-(545-617) are of similar density. Finally by yeast two-hybrid screening, we have noted no interactions between VGF or the VGF C-terminal domain and any other VGF-encoding plasmids.7
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Research reportExpression and polarization of VGF in developing hippocampal neurons

Abstract

Mol. Cell. Neurosci.

Curr. Opin. Neurobiol.

Dev. Brain Res.

Dev. Brain Res.

Cell

Curr. Opin. Cell Biol.

Neuroscience

Neuroscience

FEBS

Neuron

FEBS

Effects of stimulation of the chorda tympani in bursts on submaxillary responses in the cat

J. Physiol.

Tyrosinated and detyrosinated microtubules in axonal processes of cerebellar macroneurons grown in culture

J. Neurosci. Res.

Hippocampal synaptogenesis in cell culture: developmental time course of synapse formation, calcium influx, and synaptic protein distribution

J. Neurosci.

Characterization of GABAergic neurons in hippocampal cell cultures

J. Neurocytol.

Differential localization of MAP2 and tau in mammalian neurons in situ

Ann. NY Acad. Sci.

Growth of a rat neuroblastoma cell line in serum-free supplemented medium

Immunocytochemical localization of tubulin and microtubule-associated protein 2 during the development of hippocampal neurons in culture

J. Neurosci.

Neuronal polarity

Annu. Rev. Neurosci.

Preferential addition of newly synthesized membrane protein at axonal growth cones

Nature

Pathways to regulated exocytosis in neurons

Annu. Rev. Physiol.

Experimentally induced alterations in the polarity of developing neurons

Nature

The establishment of polarity by hippocampal neurons in culture

J. Neurosci.

The distribution of synapsin I and synaptophysin in hippocampal neurons developing in culture

J. Neurosci.

Synaptogenesis in hippocampal cultures: evidence indicating that axons and dendrites become competent to form synapses at different stages of neuronal development

J. Neurosci.

Experimental observations on the development of polarity by hippocampal neurons in culture

J. Cell Biol.

Research report
Expression and polarization of VGF in developing hippocampal neurons