# Signals Article: Putative Target P00973 for SARS-CoV-2 Long COVID Therapeutic Development
Background
SARS-CoV-2, the virus responsible for COVID-19, has led to a global pandemic with significant morbidity and mortality. A subset of individuals who recover from acute COVID-19 experience prolonged symptoms, commonly referred to as long COVID. These symptoms can include fatigue, cognitive dysfunction, respiratory issues, and other systemic manifestations that can persist for months. Understanding the underlying mechanisms of long COVID is crucial for developing effective therapeutics. A putative target candidate, P00973, has been identified through recent data-mining efforts, suggesting its potential role in the pathophysiology of long COVID and warranting further investigation.Data-mining rationale
The identification of P00973 as a putative target was derived from a comprehensive analysis of UniProt's reviewed human entries for "SARS-CoV-2 long COVID." Notably, there were no microarray datasets in the NCBI Gene Expression Omnibus (GEO) specifically tagged for long COVID. However, P00973 was found to appear in various expression-profiling studies related to COVID-19. Despite this, it lacks any registered Phase 1 or higher clinical program, indicating an opportunity for further exploration of its therapeutic potential. Additionally, many of the relevant GEO datasets predate the adoption of modern empirical-Bayes statistical methods, such as limma, suggesting that a re-analysis could yield more robust insights.Why prior analyses may have missed this
Prior analyses may have overlooked the significance of P00973 due to several factors. The absence of dedicated long COVID datasets in GEO may have limited the identification of relevant expression changes associated with this condition. Furthermore, the datasets that do exist may have been generated using older statistical methodologies that did not adequately control for multiple testing, potentially obscuring the identification of differentially expressed genes. Additionally, the complex interplay between SARS-CoV-2 infection and host immune responses in long COVID may have diluted the signal for specific targets in earlier studies.Reasoning for further validation
To validate the potential of P00973 as a therapeutic target for long COVID, the following experimental approaches are recommended: 1. **Re-analyze GEO Datasets**: Although no specific long COVID datasets were found, it is advisable to re-analyze existing COVID-19-related datasets using the limma package with Benjamini-Hochberg false discovery rate (FDR) correction set to < 0.05 to identify differentially expressed genes relevant to long COVID. 2. **Validate Differentially-Expressed Genes**: Conduct quantitative PCR (qPCR) validation of the top differentially expressed genes identified in the re-analysis using an independent cohort of long COVID patients to confirm their relevance. 3. **Check Tissue Specificity**: Investigate the tissue specificity of P00973 expression using resources such as the Genotype-Tissue Expression (GTEx) project and the Human Protein Atlas to assess its potential as a therapeutic target. 4. **Pathway Context Analysis**: Employ STRING or OmniPath databases to explore the biological pathways associated with P00973, providing context for its role in long COVID pathogenesis. 5. **Assess Druggability**: If P00973 is validated as a relevant target, evaluate its druggability using databases such as DGIdb and ChEMBL to identify potential small molecules or compounds that could be developed into therapeutics.References
- UniProt: P00973
- UniProt: Q9BYF1
- UniProt: Q96P20
- UniProt: P35613
- UniProt: Q8N3R9