Extended Data Fig. 5: Effects of Adult Myogenic Transcription Factor Loss on of Heart Tube Morphology and Function.
(A) Representative images of A2-A3 heart region visualized by phalloidin (F-Actin) with the indicated transgenes expressed under the control of the Hand-Gal4 promoter. Scale bar is 10 μm. At least three heart tubes were imaged for each condition. (B) Diastolic and (C) systolic diameters of heart tubes from control fly lines (attp40 and attp2) and their corresponding transgenic flies expressing the indicated RNAi. n = 10, 12, 18, 15, 19 and 14 (heart tubes, left to right). (D) CM nuclear area in attp2 control and LamC RNAi hearts subject to regime described in Fig. 6a. n = 29 and 22 (CM Nuclei, left to right). (E-G) Quantification of the per cell, percentage area for Hand, H15 and Tin transcripts upon KD of (E) LamC, (F) Hand (red),Tin (pink) and respective control attp2 (grey), and (G) H15 (blue) and attp40 control (grey), induced as in Fig. 6a. n = 32 and 26 (CM Nuclei/genotype) in (E), n = 20, 23, 28 (CM Nuclei/genotype, left to right) in (F) and n = 43 and 42 (CM Nuclei/genotype) in (G). (H) Schematic of temperature-sensitive transgenic expression where 29 °C enables transgenic expression due to the denaturation of Gal4 transcription factor suppressor, Gal80ts. (I) Fractional shortening of surgically exposed heart tubes at 18 °C and 29 °C for controls (black), and KD of tin (pink), Hand (brown), and H15 (blue) with corresponding diastolic and systolic diameters in (J-M). n = 13, 15, 18, 15, 26, 27, 16, 19, 29, 27, 29, and 21 (heart tubes/transgene/ temperature; left to right as shown in (I)). *p < 0.05, **p < 10−2, ***p < 10−3, and ****p < 10-4 by independent t-test and one-way ANOVA with Kruskal–Wallis test and Dunn’s comparisons test. Box plots show to min to max, with median and 25th and 75th interquartile range and error bars in (D) refer to mean + /- SD.
