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bioRxiv · 10.1101/2024.01.18.575273

High-Throughput Identification of Calcium Regulated Proteins Across Diverse Proteomes

Locke, T. M.·Fields, R.·Gizinski, H.·Otto, G. M.·Berg, M. D.·Villen, J.·Sancak, Y.·Schweppe, D. K.
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Abstract

Calcium ions play important roles in nearly every biological process, yet whole-proteome analysis of calcium effectors has been hindered by lack of high-throughput, unbiased, and quantitative methods to identify proteins-calcium engagement. To address this, we adapted protein thermostability assays in the budding yeast, human cells, and mouse mitochondria. Based on calcium-dependent thermostability, we identified 2884 putative calcium-regulated proteins across human, mouse, and yeast proteomes. These data revealed calcium engagement of novel signaling hubs and cellular processes, including metabolic enzymes and the spliceosome. Cross-species comparison of calcium-protein engagement and mutagenesis experiments identified residue-specific cation engagement, even within well-known EF-hand domains. Additionally, we found that the dienoyl-CoA reductase DECR1 binds calcium at physiologically-relevant concentrations with substrate-specific affinity, suggesting direct calcium regulation of mitochondrial fatty acid oxidation. These unbiased, proteomic analyses of calcium effectors establish a key resource to dissect cation engagement and its mechanistic effects across multiple species and diverse biological processes.

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Locke, T. M., Fields, R., Gizinski, H., Otto, G. M., Berg, M. D., Villen, J., Sancak, Y., Schweppe, D. K.. 2024-01-18. High-Throughput Identification of Calcium Regulated Proteins Across Diverse Proteomes. https://doi.org/10.1101/2024.01.18.575273

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