Imaging cytoplasmic lipid droplets in vivo with fluorescent perilipin 2 and perilipin 3 knock-in zebrafish
Abstract
Cytoplasmic lipid droplets are highly dynamic storage organelles that are critical for cellular lipid homeostasis. While the molecular details of lipid droplet dynamics are a very active area of investigation, this work has been primarily performed in cultured cells. Taking advantage of the powerful transgenic and in vivo imaging opportunities available in zebrafish, we built a suite of tools to study lipid droplets in real-time from the subcellular to the whole organism level. Fluorescently tagging the lipid-droplet-associated proteins, perilipin 2 and perilipin 3, in the endogenous loci permits visualization of lipid droplets in the intestine, liver, and adipose tissue. Using these tools, we found that perilipin 3 is rapidly loaded on intestinal lipid droplets following a high-fat meal and later replaced by perilipin 2. These powerful new tools will facilitate studies on the role of lipid droplets in different tissues, under different genetic and physiological manipulations, and in a variety of human disease models.
Data availability
All data generated during this study are included in the manuscript and supporting files; Source Data files have been provided for Figures 1, 2, 3, 4, 5, and 6.
Article and author information
Author details
Funding
National Institutes of Health (R01 DK093399)
- Steven Arthur Farber
National Institutes of Health (R01 GM63904)
- Stephen C Ekker
- Steven Arthur Farber
National Institutes of Health (F32DK109592)
- Meredith H Wilson
G. Harold and Leila Y. Mathers Foundation
- Steven Arthur Farber
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All procedures using zebrafish (Danio rerio) were approved by the Carnegie Institution Department of Embryology Animal Care and Use Committee (Protocol #139).
Copyright
© 2021, Wilson et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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- Cell Biology
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