RGD Reference Report - Upregulation of a new microglial gene, mrf-1, in response to programmed neuronal cell death and degeneration. - Rat Genome Database

Send us a Message

Submit Data |  Help |  Video Tutorials |  News |  Publications |  Download |  REST API |  Citing RGD |  Contact   

Upregulation of a new microglial gene, mrf-1, in response to programmed neuronal cell death and degeneration.

Authors: Tanaka, S  Suzuki, K  Watanabe, M  Matsuda, A  Tone, S  Koike, T 
Citation: Tanaka S, etal., J Neurosci 1998 Aug 15;18(16):6358-69.
RGD ID: 704401
Pubmed: (View Article at PubMed) PMID:9698327

Cerebellar granule neurons isolated from postnatal day 7 (P7) rats and grown in normal K+ medium begin to degenerate at approximately 4 d in vitro (DIV) and die. To search for genes upregulated in the process of neuronal cell death, differential hybridization was performed with subtracted cDNA probes and a cDNA library from 5 DIV. One of the genes isolated was microglial response factor-1 (mrf-1), which encoded a sequence of 177 amino acids with a single EF-hand calcium-binding motif. By Northern blots, the transcript was upregulated in cerebellar culture at 4 DIV, peaked at 6 DIV, and decreased at 7 DIV. Upregulation was also found when the apoptosis of granule cells was induced by replacing high K+ medium with normal K+ medium. However, when non-neuronal cells were thoroughly eliminated with aphidicolin, an antimitotic agent, the upregulation at 4-7 DIV did not occur. By immunocytochemistry, MRF-1 was detected at 5 DIV in OX-42-positive cells (microglia), and it exhibited an increase in response to granule cell death. MRF-1 levels in microglia purified from cerebral cortex also upregulated in the presence of 5 DIV granule cells. In the developing cerebellum in vivo, levels of mrf-1 mRNA transiently increased in the early postnatal stages, reaching a peak at P7 when cerebellar neurons and astrocytes undergo extensive apoptosis. In adult brain sections, MRF-1 was detected in the perikarya and processes of ramified/resting microglia, and peripheral motor nerve dissection prominently increased the expression in activated microglia surrounding injured central motoneurons. Therefore, mrf-1 appears to be one of the microglial genes that respond to neuronal cell death and degeneration.


Disease Annotations    

Gene Ontology Annotations    

Biological Process

Objects Annotated

Genes (Rattus norvegicus)
Aif1  (allograft inflammatory factor 1)

Genes (Mus musculus)
Aif1  (allograft inflammatory factor 1)

Genes (Homo sapiens)
AIF1  (allograft inflammatory factor 1)

Additional Information