ZFIN Image: Kula-Alwar et al., 2020, Fig. 3

Image

Figure Caption

Fig. 3

Mef2c is required for the formation of the heart. (A) In situ mRNA hybridisation for myl7 on 1 dpf embryos from an incross of mef2ca^+/⁻;mef2cb^+/⁻ in dorsal view, anterior to top, sequence genotyped retrospectively. Images are representative of the majority of embryos of each genotype. mef2ca^−/⁻;mef2cb^−/⁻ embryos had a severe reduction in myl7 expression. mef2ca^+/⁻;mef2cb^−/⁻ also showed a reduction in myl7 expression but to a lesser extent than double homozygous mutants. (B) Confocal stack of live hearts of mef2ca^−/−;mef2cb^−/− and its sibling on a Tg(myl7:EGFP) background. Double homozygous mutants continue to show a severe heart defect at 3 and 5 dpf but some growth in the differentiated structure is observed. (C) Heart rate measurements at 1–3 dpf for genotyped embryos showing no differences in heart rate of mef2ca^+/⁻;mef2cb^−/− embryos compared with their siblings (unpaired Student’s t-test, P > 0.05). Values are mean ± SEM. N for each group shown on bars. (D) Hearts of 52 hpf embryos from a cross of mef2ca^+/⁻;mef2cb^+/⁻ to mef2cb^−/− shown in ventral view after a double in situ hybridisation for nppa (blue) and myl7 (red). Sibling shown is mef2ca^+/+;mef2cb^+/⁻. Hearts of mef2ca^+/⁻;mef2cb^−/− are smaller and underdeveloped. Scale bars = 50 μm.

Acknowledgments

This image is the copyrighted work of the attributed author or publisher, and ZFIN has permission only to display this image to its users. Additional permissions should be obtained from the applicable author or publisher of the image.

Reprinted from Developmental Biology, 470, Kula-Alwar, D., Marber, M.S., Hughes, S.M., Hinits, Y., Mef2c factors are required for early but not late addition of cardiomyocytes to the ventricle, 95-107, Copyright (2020) with permission from Elsevier. Full text @ Dev. Biol.