title: Characterization of NGF, trkA (NGFR) , and p75 (NTR) in Retina of Mice Lacking Reelin Glycoprotein.
abstract: Both Reelin and Nerve Growth Factor (NGF) exert crucial roles in retinal development. Retinogenesis is severely impaired in E-reeler mice, a model of Reelin deficiency showing specific Green Fluorescent Protein expression in Rod Bipolar Cells (RBCs). Since no data are available on Reelin and NGF cross-talk, NGF and trkA(NGFR)/ p75(NTR) expression was investigated in retinas from E-reeler versus control mice, by confocal microscopy, Western blotting, and real time PCR analysis. A scattered increase of NGF protein was observed in the Ganglion Cell Layer and more pronounced in the Inner Nuclear Layer (INL). A selective increase of p75(NTR) was detected in most of RBCs and in other cell subtypes of INL. On the contrary, a slight trend towards a decrease was detected for trkA(NGFR), albeit not significant. Confocal data were validated by Western blot and real time PCR. Finally, the decreased trkA(NGFR)/ p75(NTR) ratio, representative of p75(NTR) increase, significantly correlated with E-reeler versus E-control. These data indicate that NGF-trkA(NGFR)/ p75(NTR) is affected in E-reeler retina and that p75(NTR) might represent the main NGF receptor involved in the process. This first NGF-trkA(NGFR)/ p75(NTR) characterization suggests that E-reeler might be suitable for exploring Reelin-NGF cross-talk, representing an additional information source in those pathologies characterized by retinal degeneration.
authors.affiliation: IRCCS-G.B. Bietti Foundation, Rome, Italy.
authors.forename: Bijorn Omar
authors.initials: BO
authors.lastname: Balzamino
authors.affiliation: Institute of Histology and Embryology, School of Medicine "A. Gemelli", Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Biamonte
authors.affiliation: IRCCS-G.B. Bietti Foundation, Rome, Italy.
authors.forename: Graziana
authors.initials: G
authors.lastname: Esposito
authors.affiliation: Laboratory of Developmental Neuroscience and Neural Plasticity, University Campus Bio-Medico, Rome, Italy.
authors.forename: Ramona
authors.initials: R
authors.lastname: Marino
authors.affiliation: Laboratory of Developmental Neuroscience and Neural Plasticity, University Campus Bio-Medico, Rome, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Fanelli
authors.affiliation: Laboratory of Developmental Neuroscience and Neural Plasticity, University Campus Bio-Medico, Rome, Italy.
authors.forename: Flavio
authors.initials: F
authors.lastname: Keller
authors.affiliation: IRCCS-G.B. Bietti Foundation, Rome, Italy ; Laboratory of Ophthalmology, IRCCS-G.B. Bietti Foundation, Via Alvaro del Portillo 21, 00128 Rome, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Micera