New Fluorescent Biosensor Reveals How Cells Manage Methionine Across Compartments
Researchers have developed a genetically encoded fluorescent biosensor called Meteor that can measure methionine levels in real time across different cellular compartments. Methionine is an essential amino acid critical for protein synthesis, redox balance, and methylation, but its subcellular dynamics were previously unmeasurable at high resolution. The tool could advance understanding of cancer metabolism and aging, given methionine's central role in cellular chemistry.
Scientists have created Meteor, a single fluorescent protein-based optical reporter designed to track the spatiotemporal dynamics of methionine within living cells and organisms. The biosensor achieves high dynamic range and subcellular resolution, enabling researchers to observe methionine uptake in compartments including the mitochondrial matrix — a location not previously accessible with existing tools. Using Meteor, the team demonstrated that cancer cells can rapidly replenish methionine from metabolic precursors in both the cytoplasm and nucleus, shedding light on how tumors sustain methionine-dependent processes. The biosensor was also validated in the model organism Caenorhabditis elegans, showing its utility for in vivo studies. Because methionine metabolism underpins methylation reactions that regulate gene expression and redox homeostasis, Meteor offers a broadly applicable platform for studying disease, aging, and cellular stress responses.
What's missing
As a preprint on bioRxiv, this work has not yet undergone formal peer review. Generalizability to mammalian in vivo models beyond C. elegans remains undemonstrated.
What different sources said
- bioRxivCenter
Revealing the spatiotemporal dynamics of methionine metabolism with a genetically encoded single-fluorophore biosensor
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