Figure 8

Zebrafish eif2b5 mutant alleles show intron retention, activated ISR, and role of truncated Eif2b5 in worsening phenotype. (A) Schematic showing integrated stress response activated intron 12 retention of eif2b5 resulting in premature stop codon and truncated form of EIF2B5. (B) Fold change of eif2b5 intron 12 expression with qRT-PCR in eif2b5^zc103/zc103, eif2b5^zc102/zc102, and eif2b2^{sa17223/sa17223} mutants relative to controls. (C) qRT-PCR for intron 12 expression in a VWM patient and their control unaffected father. (D) Control-injected larvae, compared to those injected with truncated eif2b5 construct, shows impaired swimming behavior; distance moved, time spent moving, and velocity, at 5 dpf. (E) qRT-PCR for atf4, bip, chopII, and perk ISR transcripts shows increased expression in eif2b5^zc103/zc103, eif2b5^zc102/zc102, and eif2b2^{sa17223/sa17223} mutants. (F) qRT-PCR for ISR transcripts (atf 4, bip, chop II, and perk) shows increased expression following injection of truncated eif2b5 construct.