title: The expression analysis of mouse interleukin-6 splice variants argued against their biological relevance.
abstract: Alternative splicing generates several interleukin-6 (IL-6) isoforms; for them an antagonistic activity to the wild-type IL-6 has been proposed. In this study we quantified the relative abundance of IL-6 mRNA isoforms in a panel of mouse tissues and in C2C12 cells during myoblast differentiation or after treatment with the Ca(2+) ionophore A23187, the AMP-mimetic AICAR and TNF-α. The two mouse IL-6 isoforms identified, IL-6δ5 (deletion of the first 58 bp of exon 5) and IL-6δ3 (lacking exon 3), were not conserved in rat and human, did not exhibit tissue specific regulation, were expressed at low levels and their abundance closely correlated to that of full-length IL-6. Species-specific features of the IL-6 sequence, such as the presence of competitive 3' acceptor site in exon 5 and insertion of retrotransposable elements in intron 3, could explain the production of IL-6δ5 and IL-6δ3. Our results argued against biological significance for mouse IL-6 isoforms.
authors.affiliation: Dipartimento di Scienze Biomolecolari, Universita degli Studi di Urbino Carlo Bo, Italy. giosue.annibalini@uniurb.it
authors.forename: Giosuè
authors.initials: G
authors.lastname: Annibalini
authors.forename: Michele
authors.initials: M
authors.lastname: Guescini
authors.forename: Deborah
authors.initials: D
authors.lastname: Agostini
authors.forename: Rita De
authors.initials: RD
authors.lastname: Matteis
authors.forename: Piero
authors.initials: P
authors.lastname: Sestili
authors.forename: Pasquale
authors.initials: P
authors.lastname: Tibollo
authors.forename: Michela
authors.initials: M
authors.lastname: Mantuano
authors.forename: Chiara
authors.initials: C
authors.lastname: Martinelli
authors.forename: Vilberto
authors.initials: V
authors.lastname: Stocchi
mesh_terms: D017398:Alternative Splicing / Q000235:genetics*; D000818:Animals; D002478:Cells, Cultured; D005260:Female; D014644:Genetic Variation / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D015850:Interleukin-6