Fig. S4

a, b Sequence comparison of the unc45b region mediating the misfolded myosin response with homologous regions in the unc45b genes of other fish species. a Scheme of the 195-bp zebrafish unc45b fragment (-505 to -310 relative to the ATG) containing the HSE at position -446/-422 and the Mef2 binding site at position -335/-313. The recognition sequence is depicted below each site. b Comparison of the zebrafish unc45b sequence from -505 to -310 with regions in the unc45b genes of four other fish species revealed the presence of a conserved HSE element (black ovals). c–e Injection of -505/-405(unc45b)gata2:gfp plasmid into wild-type embryos (cont) (c) do not generate any GFP expression, whereas co-injection with unc45b-mo activates the regulatory sequence (c) (unc45b-mo). Examination of the GFP fibrils revealed classic striations (d, e, z) (Z-line). f injection of -505/-405(unc45b)gata2:gfp plasmid into hel mutant (hel/) or wild-type siblings (cont) do not lead to GFP0 expression. g, h Injection of -505/-310(unc45b)gata2:gfp plasmid into wild type (cont) (g, h), unc45b morphant (unc45b-mo) (g) or hel mutants (hel/) (h) show a GFP upregulation in unc45b morphant but not in hel mutants.