Journal: bioRxiv
Article Title: Active and Passive Mechanical Deficits Precede Spinal Curvature in a Zebrafish Model of Idiopathic Scoliosis
doi: 10.64898/2026.04.29.721663
Figure Lengend Snippet: Active force generation is reduced in 5 d.p.f. uts2r3 mutant larval trunks. (A) Schematic of the ex vivo larval trunk mechanics assay. Isolated 5 d.p.f. preparations were mounted between a length motor and force transducer for mechanical testing. Sarcomere striations were visualized and used to measure muscle length before mechanical assessment. (A’) Representative image of a mounted 5 d.p.f. trunk preparation, with the expanded view showing sarcomere striations. (B) Cross-sectional area of larval trunk preparations, calculated from dorsal-ventral and lateral diameter measurements assuming an elliptical cross section. Cross-sectional area did not differ between wild-type and uts2r3 mutant specimens ( p = 0.495; WT, n = 10; uts2r3 , n = 11). (C) Maximal tension generated during twitch and tetanic stimulation. uts2r3 mutants generated reduced tension compared with wild type, with a significant reduction during tetanic stimulation. WT, n = 9; uts2r3 , n = 10. (D) Maximal force generated during twitch and tetanic stimulation. uts2r3 mutants generated significantly less force under both stimulation conditions. WT, n = 9; uts2r3 , n = 10. (E) Force depression during shortening contractions, expressed as percent reduction from isometric force at the same length. No significant differences were detected across contractile velocities. WT, n = 8; uts2r3 , n = 7. Bars show means ± SD with individual specimens shown as points.
Article Snippet: Stimulation was provided using a constant-current stimulation device (Aurora Scientific), with supramaximal current determined independently for each sample preparation before mechanical assessment.
Techniques: Mutagenesis, Ex Vivo, Isolation, Generated