Proteomic Characterization of Spinal Cord Myelin in the Mouse.

The myelin proteome is a critical structural and functional component of the central nervous system (CNS), undergoing dynamic remodeling throughout life. Pathological changes, such as those in multiple sclerosis, disrupt myelin integrity and lead to severe neurological deficits. Establishing a reproducible baseline of the CNS myelin proteome is therefore essential for monitoring alterations in disease models. Here, we present a comprehensive proteomic dataset of purified spinal cord myelin from healthy mice. Myelin fractions were isolated by preparative sucrose density centrifugation, followed by gel-free peptide separation and mass spectrometric analysis. Label-free quantification based on at least two tryptic peptides identified 725 proteins across six spinal cord samples. Comparison with previous large-scale datasets confirmed the robustness of our workflow. In particular, our dataset showed a 71% overlap with the 809 proteins identified by Jahn et al. using a highly similar proteomic approach. Importantly, there was near-complete agreement for canonical myelin proteins, validating both the specificity and reproducibility of our method. Beyond this shared core, our dataset contributed additional proteins, including axon- and glia-associated candidates, expanding the baseline repertoire of the spinal cord myelin proteome. In summary, this study establishes and validates a reliable workflow for spinal cord myelin proteomics and provides a reproducible reference dataset. While not yet including diseased tissue, this baseline is directly applicable to experimental models of demyelination and remyelination, offering a critical foundation for detecting and interpreting disease-related proteomic alterations in multiple sclerosis research.