We investigated the involvement of ubiquitin in the neuronal response to axonal injury in the quail parasympathetic ciliary ganglion by immune-light and electron microscopy. Image analysis of immunoreacted cryosections shows that ubiquitin-immunoreactivity in the ciliary neurons increases significantly 6 hours after postganglionic nerve crush. The immunolabeling reaches a peak 1 day after injury and begins to decrease between days 3 and 6 when, in contrast to the cytoplasm, numerous highly eccentric nuclei are strongly immunolabeled. Electron microscopy shows ubiquitin-immunoreactivity associated with cytoplasmic organelles and with several postsynaptic densities of the numerous synapses established by the preganglionic boutons on the soma of the ciliary neurons. The number of immunopositive postsynaptic densities increases significantly 1 day after axonal damage, followed by temporary detachment of the preganglionic boutons from the injured neurons between days 3 and 6. The early increase in cytoplasmic ubiquitin-immunoreactivity suggests a prompt ubiquitination of damaged proteins addressed to degradation, while the nuclear immunolabeling may reflect high histone ubiquitination, a process involved in keeping chromatin transcriptionally active. The possible ubiquitin-mediated removal of postsynaptic apparatus constituents such as ACh receptors, proteins involved in their clustering and stabilization, and/or adhesion molecules may be a crucial step for the detachment of the preganglionic boutons, thus favoring injury-induced synaptic plasticity.

The rise in cytoplasmic ubiquitin levels is an early step in the response of parasympathetic ganglionic neurons to axonal injury followed by regeneration / DE STEFANO, Maria Egle; Rosanna, Squitti; Toschi, Giovanni. - In: JOURNAL OF NEUROPATHOLOGY AND EXPERIMENTAL NEUROLOGY. - ISSN 0022-3069. - STAMPA. - 57:11(1998), pp. 1000-1012. [10.1097/00005072-199811000-00002]

The rise in cytoplasmic ubiquitin levels is an early step in the response of parasympathetic ganglionic neurons to axonal injury followed by regeneration

DE STEFANO, Maria Egle;TOSCHI, Giovanni
1998

Abstract

We investigated the involvement of ubiquitin in the neuronal response to axonal injury in the quail parasympathetic ciliary ganglion by immune-light and electron microscopy. Image analysis of immunoreacted cryosections shows that ubiquitin-immunoreactivity in the ciliary neurons increases significantly 6 hours after postganglionic nerve crush. The immunolabeling reaches a peak 1 day after injury and begins to decrease between days 3 and 6 when, in contrast to the cytoplasm, numerous highly eccentric nuclei are strongly immunolabeled. Electron microscopy shows ubiquitin-immunoreactivity associated with cytoplasmic organelles and with several postsynaptic densities of the numerous synapses established by the preganglionic boutons on the soma of the ciliary neurons. The number of immunopositive postsynaptic densities increases significantly 1 day after axonal damage, followed by temporary detachment of the preganglionic boutons from the injured neurons between days 3 and 6. The early increase in cytoplasmic ubiquitin-immunoreactivity suggests a prompt ubiquitination of damaged proteins addressed to degradation, while the nuclear immunolabeling may reflect high histone ubiquitination, a process involved in keeping chromatin transcriptionally active. The possible ubiquitin-mediated removal of postsynaptic apparatus constituents such as ACh receptors, proteins involved in their clustering and stabilization, and/or adhesion molecules may be a crucial step for the detachment of the preganglionic boutons, thus favoring injury-induced synaptic plasticity.
1998
axon regeneration; axotomy; ciliary ganglion; image analysis; immunocytochemistry; nerve injury; quail ciliary ganglion; synaptic remodeling; ubiquitin
01 Pubblicazione su rivista::01a Articolo in rivista
The rise in cytoplasmic ubiquitin levels is an early step in the response of parasympathetic ganglionic neurons to axonal injury followed by regeneration / DE STEFANO, Maria Egle; Rosanna, Squitti; Toschi, Giovanni. - In: JOURNAL OF NEUROPATHOLOGY AND EXPERIMENTAL NEUROLOGY. - ISSN 0022-3069. - STAMPA. - 57:11(1998), pp. 1000-1012. [10.1097/00005072-199811000-00002]
File allegati a questo prodotto
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/42962
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus 4
  • ???jsp.display-item.citation.isi??? 3
social impact