FIGURE 4.

Twelve known isoforms of human GFAP. GFAPα (canonical isoform) comprises 9 exons represented as rounded rectangles. Respective exons and splice junctions were mapped to the amino acid sequence of GFAPα using the CCDS (NCBI) database (Pujar et al., 2018). GFAPβ and γ isoforms originate from alternative transcription start sites and have a varied N‐terminal (head). The rest of the isoforms result from alternative splicing: δ /ε, κ, and μ have shortened C‐terminal (tail), λ and ζ have alternate rod domains and less common GFAP +1 isoforms have shortened rod domains. Stars represent introns and yellow rounded rectangles indicate alternate regions. Longer linkers in the last two cases of GFAP+1 isoforms indicate that GFAP∆Ex6 lacks exon 6 and GFAP∆Ex7 lacks exon 7. Question marks indicate that the exact start sites of these isoforms are not yet known. Adapted from Middeldorp & Hol (2011), de Reus et al. (2024), and Yang & Wang (2015).