Desk screen

Desk Screen Assessment

Scope and Fit

This manuscript describes activity-based protein profiling (ABPP) of primary mouse brain cells to identify covalent ligands for CNS-enriched proteins, with detailed characterization of ligands targeting HCN channels. The work is original research with empirical, methodological, and functional components. It clearly fits In Silico's scope as research whose claims can be evaluated from the manuscript and deposited materials.

Threshold Issues

Completeness of submission: The manuscript is complete with methods, results, figures, supplementary data, and materials availability statement. Data have been deposited to ProteomeXchange (PXD082934).

Fundamental soundness: The experimental design is coherent. The authors:

• Establish a new ABPP protocol for intact primary brain cells
• Perform both gel-based and MS-based proteomics with appropriate controls
• Validate findings across multiple cell types and preparations
• Conduct functional studies (patch clamp, IP-MS) to support mechanistic claims
• Acknowledge limitations explicitly (e.g., disassociated cells vs. in vivo, rare cell types)

Evidence-claim alignment: The central claims are appropriately scaled to the evidence:

• The brainocyte ABPP platform is demonstrated to work and to identify proteins not seen in prior studies
• Stereoprobe liganding is validated through site-directed mutagenesis, competitive blockade, and ortholog testing
• HCN channel functional effects are shown in heterologous systems, inside-out patches, and native neurons
• The authors do not overclaim; they note that cysteine mutant HCN channels showed unexpected dysfunction and do not fully understand why

Checkability: Methods are detailed. Proteomics data are deposited. Plasmids are available via MTA. Procedures are sufficiently described for reproduction.

Minor Observations

• The work is technically sophisticated and the manuscript is well-written, but this is not a threshold issue for desk screen
• Some claims rest on inference (e.g., that brainocyte-restricted liganding reflects authentic cell-dependent interactions), but the authors test this with brain slices and acknowledge uncertainty
• The functional impact of most liganded proteins is not characterized, but this is presented as future work, not claimed

Decision

The manuscript presents sound, original research with appropriate scope, complete data, and honest reporting of limitations. It should proceed to full review.

DESK DECISION: proceed