Unravelling Novel SCN5A Mutations Linked to Brugada Syndrome: Functional, Structural, and Genetic Insights
, Emanuele Micaglio 1,2, Ivan Polsinelli 1, Serena Calamaio 1, Dario Melgari 1, Rachele Prevostini 1, Andrea Ghiroldi 1,3, Anna Binda 4, Paola Carrera 5, Marco Villa 1, Flavio Mastrocinque 2, Silvia Presi 5, Raffaele Salerno 6, Antonio Boccellino 2, Luigi Anastasia 1,3,6, Giuseppe Ciconte 1,2,6, Stefano Ricagno 1,7, Carlo Pappone 1,2,6 and Ilaria Rivolta 1,4,*
Changmin Peng
Round 1
Reviewer 1 Report
I have carefully reviewed the manuscript titled "Unravelling novel SCN5A mutations linked to Brugada Syndrome: Functional, Structural, and Genetic Insights" submitted for publication in the International Journal of Molecular Sciences. The authors have presented a detailed study on the complexities associated with Brugada syndrome (BrS), emphasizing the multifaceted approaches required for its clinical management. The confluence of in silico predictions, structural modeling, functional tests, and drug testing offers a comprehensive perspective on BrS, especially concerning SCN5A mutations.
Notable strengths of the manuscript include:
Technical Depth and Rigor: The authors have demonstrated strong experimental methodology, which is substantiated by relevant conclusions.
Interdisciplinary Approach: By amalgamating diverse research tools and methodologies, the manuscript provides an enriched understanding of the topic.
Clinical Relevance: Discussions on personalized medical approaches and tailored treatment strategies impart valuable insights that have the potential to benefit the wider medical community.
However, while the manuscript stands out in its depth and execution, addressing the following points could further elevate its quality. If certain aspects cannot be addressed experimentally, providing a detailed explanation would be deemed acceptable:
Broader Study on Patient Samples: Expanding the genetic sequencing to include a larger cohort of BrS patients could offer deeper insights into the clinical relevance of SCN5A mutations.
Utilization of Disease Models: The incorporation of BrS animal models or induced pluripotent stem cells (iPSC)-derived cardiomyocytes might validate the impacts of specific mutations or therapeutic interventions within a more intricate biological system.
Multifactorial Analysis: Given the potential oligogenic inheritance of BrS, a broader multi-genomic exploration could unravel other gene mutations or factors associated with the disease's manifestation.
In-depth Structural Analysis: Harnessing advanced structural biology methods like cryo-EM or X-ray crystallography can provide a granular view of SCN5A, aiding in deciphering the functional implications of mutations.
In conclusion, given the robustness and relevance of the presented research, I advocate for the manuscript's acceptance in the International Journal of Molecular Sciences post addressing the proposed minor revisions.
Author Response
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Reviewer 2 Report
This is one of the most polished paper which I have reviewed in a long time, and as such I only have minor comments.
1) can n numbers please be added to figure and table legends.
2) can the authors comment on transfection efficacy (ie how to you know that the results are not influenced by differential transfection/translation.
Author Response
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Reviewer 3 Report
The authors identified 3 novel SCN5A mutations linked to Brugada Syndrome in three families. The SCN5A protein with each of the mutations were expressed in HEC cells and the channel function was characterized. The authors also considered possible mechanistic bases for how these mutations might affect the SCN5A channel function. Overall, this is an interesting study that is done competently. I have several minor comments.
1. Line 55. EGC should be ECG.
2. Lines 152-154. The authors state, “In the experimental conditions that mimicked the genetic background of the patients’, thus a 1:1 ratio between mutated and WT channel, a significant reduction of peak current density was commonly observed.” How was this 1:1 ration determined in the experiment?
3. Figure 3. These confocal images lack the crispiness of normal confocal images, especially using a 63x objective lens. Please present better images. Presumably, these images are a single optical section, not through-focused images. Please specify. To show membrane localization of mutant proteins, please show GFP images, not immunofluorescence images that show both WT and mutants.
4. Figure 4B. Two of the 6 measurements show wide current density distributions. Please explain why. Is the reason technical or functional (i.e. physiological and expected)?
5. The structural analysis section could be moved to discussion as the content of many parts of this section fits better in discussion. However, the choice is for the authors to make.
6. Lines 232 and 243. Figure 1A is cited, but I do not believe this is correct.
7. The conclusion section should contain main take-home messages of the study. At present, this section sounds like continuation of discussion and even new ideas, such as caveats, are discussed. These caveats must be moved to discussion.
Only minor editing
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