Immunoproteasome responds to injury in the retina and brain.
It is well known that immunoproteasome generates peptides for MHC Class I occupancy and recognition by cytotoxic T lymphocytes (CTL). The present study focused on evidence for alternative roles for immunoproteasome. Retina and brain were analyzed for expression of immunoproteasome subunits using immunohistochemistry and western blotting under normal conditions and after injury/stress induced by CTL attack on glia (brain) or neurons (retina). Normal retina expressed substantial levels of immunoproteasome in glia, neurons, and retinal pigment epithelium. The basal level of immunoproteasome in retina was two-fold higher than in brain; CTL-induced retinal injury further up-regulated immunoproteasome expression. Immunoproteasome up-regulation was also observed in injured brain and corresponded with expression in Purkinje cells, microglia, astrocytes, and oligodendrocytes. These results suggest that the normal environment of the retina is sufficiently challenging to require on-going expression of immunoproteasome. Further, immunoproteasome up-regulation with retinal and brain injury implies a role in neuronal protection and/or repair of damage.
Ferrington
Deborah A
DA
Department of Ophthalmology, University of Minnesota, Minneapolis, Minnesota, USA. ferri013@umn.edu
Hussong
Stacy A
SA
Roehrich
Heidi
H
Kapphahn
Rebecca J
RJ
Kavanaugh
Shannon M
SM
Heuss
Neal D
ND
Gregerson
Dale S
DS
D000818:Animals; D001921:Brain / Q000276:immunology* / Q000503:physiopathology; D002450:Cell Communication / Q000276:immunology; D004660:Encephalitis / Q000276:immunology* / Q000503:physiopathology; D051379:Mice; D008822:Mice, Transgenic; D009410:Nerve Degeneration / Q000276:immunology / Q000503:physiopathology; D009416:Nerve Regeneration / Q000276:immunology; D009457:Neuroglia / Q000276:immunology / Q000473:pathology; D009473:Neuronal Plasticity / Q000276:immunology; D009474:Neurons / Q000276:immunology / Q000473:pathology; D010857:Pigment Epithelium of Eye / Q000276:immunology / Q000503:physiopathology; D046988:Proteasome Endopeptidase Complex / Q000276:immunology*; D021122:Protein Subunits / Q000276:immunology; D020127:Recovery of Function / Q000276:immunology; D012160:Retina / Q000276:immunology* / Q000503:physiopathology; D012173:Retinitis / Q000276:immunology* / Q000503:physiopathology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D015854:Up-Regulation / Q000276:immunology
D021122:Protein Subunits; D046988:Proteasome Endopeptidase Complex