Schematic representation of the different mouse GFAP isoforms studied.

<p>The scheme illustrates the differential splicing routes resulting in 10 different Gfap transcript isoforms. The 9 exons containing the canonical Gfap-α isoform is shown on top. Size of the depicted exons is to scale except for exon 1 and 9, indicated by breaks. The target position of primers used for qPCR assays are indicated (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042823#pone.0042823.s002" target="_blank">Table S1</a> for their sequences). The position of the epitope for the isoform-specific antibodies generated by us is indicated. Note that only the full-length sequences of mouse Gfap-α, Gfap-δ <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042823#pone.0042823-Roelofs1" target="_blank">[25]</a>, and Gfap-κ <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042823#pone.0042823-Blechingberg1" target="_blank">[26]</a> were identified by us. Transcripts encoding for GfapΔ135, and the GFAP+1 variants (GfapΔ164 and GfapΔEx6), as found in human brain <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042823#pone.0042823-Hol1" target="_blank">[24]</a>, were not detected by qPCR. We found evidence for the existence of GfapΔEx7, a potential GFAP+1 variant, but no effort was made to clone the full-length sequence. Gfap-δ and Gfap-κ each encode for a unique C-terminal amino acid sequence of 41 aa and 46 aa, respectively, different from the Gfap-α encoded C-terminus. Gfap-β was decribed for rat brain <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042823#pone.0042823-Feinstein1" target="_blank">[21]</a>, Gfap-γ and Gfap-ζ were isolated from mouse brain <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042823#pone.0042823-Zelenika1" target="_blank">[23]</a>.