Ilf3 and NF90 associate with the axonal targeting element of Tau mRNA.
In neurons, the selective translocation of Tau mRNA toward axons is due to the presence of a nucleotide sequence located in its 3' untranslated region and serving as axonal targeting element. Using this RNA sequence as a probe by a Northwestern approach, we have detected several proteins that interact with the targeting RNA element and could potentially be involved in Tau mRNA translocation, translation halting, and/or stabilization. Among them, two proteins were identified as the interleukin enhancer binding factor 3 (Ilf3) and NF90, two isoforms derived from a single gene product through alternative splicing. Each protein comprises two double-stranded RNA binding motifs that can interact with the predicted stem-loop secondary structure of the axonal targeting element. Specific antibodies raised against common or specific peptide sequences showed that both Ilf3 and NF90 are polymorphic proteins that are detected in neuronal nuclei and cell bodies, as well as in the proximal neuritic segments. This observation favors the idea that Ilf3 and NF90 are part of a protein complex that escorts Tau mRNA toward the axon.
Larcher
Jean-Christophe
JC
Biochimie Cellulaire-CNRS UMR 7098, Université Paris-6, 9 quai Saint-Bernard, Bâtiment C-Case 265, Paris 75252, Cedex 05, France. jclarche@snv.jussieu.fr
Gasmi
Laila
L
Viranaïcken
Wildriss
W
Eddé
Bernard
B
Bernard
Rozenn
R
Ginzburg
Irith
I
Denoulet
Philippe
P
D020413:3' Untranslated Regions; D000818:Animals; D000918:Antibody Specificity; D001369:Axons / Q000378:metabolism*; D001692:Biological Transport; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000302:isolation & purification / Q000378:metabolism; D007150:Immunohistochemistry; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000302:isolation & purification; D050778:NFATC Transcription Factors; D009474:Neurons / Q000737:chemistry / Q000378:metabolism; D050779:Nuclear Factor 90 Proteins; D009687:Nuclear Proteins / Q000032:analysis* / Q000302:isolation & purification / Q000378:metabolism; D015347:RNA Probes; D012333:RNA, Messenger / Q000737:chemistry / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000032:analysis* / Q000276:immunology / Q000302:isolation & purification; D038621:Regulatory Sequences, Ribonucleic Acid; D020539:Sequence Analysis, Protein; D014157:Transcription Factors / Q000032:analysis* / Q000302:isolation & purification / Q000378:metabolism; D016875:tau Proteins / Q000235:genetics* / Q000378:metabolism
D020413:3' Untranslated Regions; D004268:DNA-Binding Proteins; C494015:Ilf3 protein, mouse; D008869:Microtubule-Associated Proteins; D050778:NFATC Transcription Factors; D050779:Nuclear Factor 90 Proteins; D009687:Nuclear Proteins; D015347:RNA Probes; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D038621:Regulatory Sequences, Ribonucleic Acid; D014157:Transcription Factors; D016875:tau Proteins