Quantification of autophagy flux in isolated mouse skeletal muscle fibers with overexpression of fluorescent protein mCherry-EGFP-LC3

STAR Protoc. 2023 Mar 17;4(1):101871. doi: 10.1016/j.xpro.2022.101871. Epub 2023 Jan 23.

Abstract

Evaluation of autophagy flux could be challenging for muscle fibers due to the baseline expression of mCherry-EGFP-LC3 along the Z-line. We established a protocol to overcome this difficulty. We overexpress mChery-EGFP-LC3 in the FDB muscle of an adult mouse via electroporation. Then, we enzymatically digest FDB muscle to yield individual fibers for live cell imaging. Finally, we develop an ImageJ-based program to eliminate the baseline striation pattern and semi-automatically quantify autophagosomes (APs) and autolysosomes (ALs) for autophagy flux analysis.

Keywords: Cell Biology; Microscopy; Model Organisms.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Autophagosomes / metabolism
  • Autophagy* / genetics
  • Coloring Agents / metabolism
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Mice
  • Microtubule-Associated Proteins* / genetics
  • Microtubule-Associated Proteins* / metabolism
  • Muscle Fibers, Skeletal / metabolism

Substances

  • Microtubule-Associated Proteins
  • Green Fluorescent Proteins
  • Coloring Agents