Journal: iScience
Article Title: The Drosophila Him gene is essential for adult muscle function and muscle stem cell maintenance
doi: 10.1016/j.isci.2026.114670
Figure Lengend Snippet: Him is required for normal jump muscle morphology and function, and genetically interacts with Mef2 (A–H) Transverse cryosections of adult jump muscle labeled with anti-βPSintegrin (green) and Hoechst nuclear stain (blue). (A) Control ( yw;;nos-Cas9 ) jump muscle section ( n = 12) consists of two organized rows of muscle fibers arranged around a mid-line (white arrow). The WT morphology is disrupted in 100% of (B) Him 0 mutant ( n = 12), (C) Him 52 mutant ( n = 7), and (D) Him 0 /Him 52 heteroallelic mutant flies ( n = 7). Him mutants have “internal fibers” that do not contact the outer edge of the jump muscle (orange arrow in B). Both the HimGFP minigene and the Him duplication restore WT morphology in Him 0 (E,G) and Him 52 (F,H) mutants ( n = 8–11 per genotype). Scale bars, 50 μm. (I) Bar graph showing mean internal muscle fiber counts ±SEM of the genotypes in (A–H). Him mutants have significantly more internal fibers than WT. Both Him GFP and the Him duplication restore counts to WT values. (Kruskal-Wallis followed by post hoc Dunn’s test: p < 0.001, control versus Him 52 ∗∗∗ p < 0.001, control versus Him 0 ∗∗∗ p < 0.001, control versus Him 52 / Him 0 ∗∗∗ p < 0.001, control versus Him 52 ;; Him GFP p = 0.5985 (n.s.), control versus Him 52 ; ; Him Dup p = 0.2506 (n.s.), control versus Him 0 ;; Him GFP p = 0.2784 (n.s.), control versus Him 0 ;; Him Dup n = 0.2506 (n.s.). (J–L) Transverse cryosections of (J) control ( yw;;nos-Cas9 n = 11), (K) Him 0 mutant ( n = 6) and (L) Him 0 ; Mef2 22.21 /+ flies ( n = 11). Scale bars, 50 μm. The Mef2 22.21 allele rescues the Him mutant morphology toward WT. (M) Bar graph showing mean internal muscle fiber counts ±SEM of the genotypes in (K–M). Him 0 ;Mef2 22.21 /+ flies have significantly fewer internal fibers than Him 0 mutants, but more internal fibers than control flies (Kruskal-Wallis followed by post hoc Dunn’s test: p < 0.001, control versus Him0 ∗∗∗ p < 0.001, control versus Him0;Mef2 22.21 /+ ∗∗ p = 0.0012, Him 0 versus Him0;Mef2 22.21 /+ ∗ p = 0.0363). (N) Bar graph showing mean horizontal jump ±SEM, in response to a looming stimulus ( n = 15–20 flies per genotype). Him 0 and Him 52 adults jump significantly less distance than yw;;nosCas9 controls. HimGFP rescues each Him mutant to WT phenotype. (ANOVA followed by post hoc Dunnett’s test: ANOVA p < 0.0001, control versus Him 0 ∗ p = 0.0151, control versus Him 0 ;; Him GFP/+ non-significant (n.s.) p = 0.7185, control versus Him 52 ∗∗∗ p = 0.0001, control versus Him 52 ; Him GFP/+ n.s. p > 0.9999).
Article Snippet: Rabbit anti-Mef2 (1:1,000) , DSHB , Mef2.
Techniques: Labeling, Staining, Control, Mutagenesis