While hundreds of different lipids have been identified in human blood, many of them remain functionally uncharacterized, including a class of lipids called long-chain acylcarnitines (LCACs). The use of elevated LCACs as a biomarker for type II diabetes, obesity and aging, as well as their association with normal states of exercise and cold exposure will be discussed. We will then discuss the toxicity of LCACs to many cell types and how we have exploited this toxicity to perform a genome-wide CRISPR screen in HEK293T cells to identify genes associated with LCAC function, regulation and intracellular processing. The use of molecular biology methods within these screens will be highlighted before reviewing our key findings, which include the identification of the transmembrane protein CD36 as being necessary for resistance to LCAC toxicity. The implications and potential use of LCACs, beyond their current use as a biomarker for metabolic dysregulation, will be discussed.

Learning Objectives:

1. Summarize the key steps and considerations in electrophoresis of nucleic acids.

2. Investigate the toxicity of LCACs to various cell types and how genome-wide CRISPR screens were used to identify genes related to LCAC function, regulation, and intracellular processing.

3. Discuss the potential of LCACs beyond metabolic dysregulation, including the identification of CD36 as a key protein for resistance to LCAC toxicity, and implications for future research and clinical applications.