Generation of MLC-2v-tdTomato knock-in reporter mouse line

Genesis. 2018 Oct;56(10):e23256. doi: 10.1002/dvg.23256. Epub 2018 Nov 2.

Abstract

MLC-2v is a myosin light chain regulatory protein which is specifically expressed in ventricular cardiomyocytes and slow twitch skeletal muscle cells. MLC-2v plays critical roles in ventricular maturation during heart development. Mice lacking MLC-2v are embryonic lethal due to heart failure associated with abnormal myofibrillar organization of ventricular cardiomyocytes. To study the development of ventricular cardiac muscle and slow twitch skeletal muscle, we generated a new MLC-2v reporter mouse line by knocking-in a tdTomato reporter cassette into 3' UTR of the MLC-2v gene without disrupting the endogenous gene. Our results demonstrated specific MLC-2v-tdTomato knock-in reporter expression in ventricular cardiomyocytes and slow twitch muscle during myogenesis, precisely recapitulating the spatiotemporal expression pattern of endogenous MLC-2v. No tdTomato expression was observed in the atria, fast twitch muscle or other organs throughout development into adulthood. Isolated neonatal and adult ventricular cardiomyocytes uniformly express tdTomato. Taken together, MLC-2v-tdTomato knock-in reporter mouse model described in this article will serve as a valuable tool to study cardiac chamber and skeletal muscle specification during development and regeneration by overcoming the pitfalls of transgenic strategies.

Keywords: MLC-2v; heart; muscle; ventricle.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Gene Knock-In Techniques
  • Genes, Reporter*
  • Lycopersicon esculentum / genetics
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred Strains
  • Mice, Transgenic
  • Myosin Light Chains / genetics*
  • Myosin Light Chains / physiology

Substances

  • Mylpf protein, mouse
  • Myosin Light Chains