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De Oliveira Rosa, N.

Publications and source records attributed to De Oliveira Rosa, N..

4 recordsLinked to original sources

Atlantis: An integrative database for human proteome structural and functional sites

Understanding protein mechanisms in health and disease requires characterizing the functional roles of individual amino acid residues. To explore the role of residues and their mutations, we have developed Atlantis, a database that integrates structural and functional information at the human proteome residue level. A graph database enables complex queries and the retrieval of integrated information for multiple functional analysis of protein systems. A Model Context Protocol (MCP) connector allows the interrogation of the resource through Large Language Models (LLMs) or agentic frameworks for biomedical research. Atlantis annotates over 11M residues across 20k human proteins, identifying hundreds thousands intra- and inter-protein contacts in PDB as well as AlphaFoldDB structures. We also provide the possibility to analyze and integrate predicted 3D complexes inputted by the user, and we showcased these features on hundreds of AlphaFold-multimer complexes of GPCRs and LRRK2 interaction networks. The tool is freely accessible at https://atlantis.bioinfolab.sns.it/.

bioinformatics↗

Dissection of Gαs and Hedgehog signaling crosstalk reveals therapeutic opportunities to target adenosine receptor 2b in Hedgehog-dependent tumors

Basal cell carcinoma (BCC), the most common human cancer, is driven by hyperactivation of Hedgehog Smoothened (SMO) and GLI transcription. Gs and protein kinase A (PKA) negatively regulate Hedgehog signaling, offering an alternative BCC development and treatment pathway. Here, using histology alongside bulk and single-cell RNA sequencing, we find that mouse BCC-like tumors that originate from Gs pathway inactivation are strikingly similar to those driven by canonical Hedgehog SMO. Interestingly, mutations that reduce Gs and PKA activity are present in human BCC. Tumors from Gs pathway inactivation are independent of the canonical Hedgehog regulators SMO and GPR161, establishing them as an SMO-independent oncogenic Hedgehog signaling model. Finally, we demonstrate that activation of the Gs-coupled adenosine 2B receptor counteracts oncogenic SMO, reducing Hedgehog signaling and tumor formation and offering a potential therapeutic strategy for BCC.

cancer biology↗

Proximity proteomics reveals a co-evolved LRRK2-regulatory network linked to centrosomes

Leucine-rich repeat kinase 2 (LRRK2) not only plays a vital role in familial forms of Parkinsons disease (PD) but also represents a risk factor for idiopathic PD. Its multi-domain architecture enables fine-tuned regulation of its biological function by orchestrating intra- and intermolecular interactions. Here, we present BioID proximity proteomes of LRRK2 that reveal new interactors, which we further characterize using a novel evolutionary and structural bioinformatics pipeline. Co-evolutionary analysis of the protein-protein interaction network identifies a structural and functional module enriched in cytoskeletal components associated with the centrosome and microtubules. In addition, structural modelling of binary interactions using AlphaFold-Multimer reveals distinct groups of interactors that engage LRRK2 in a manner dependent on specific conformations and epitopes. Furthermore, we identify distinct changes in the LRRK2 proximity proteome that are induced by the type I kinase inhibitor MLi-2 or by co-expression of the LRRK2 upstream effector RAB29. Depending on its activity state and conformation, these protein-protein interactions link LRRK2 to defined cellular sub-compartments, including centriolar satellites and vesicular sub-compartments. SummaryThis study defines a comprehensive, LRRK2 interaction network by combining proximity proteomics with evolutionary and structural analyses, revealing how LRRK2 conformation and activity state dictate distinct protein-protein interactions. These findings link LRRK2 to conserved centrosomal, cytoskeletal, and vesicular pathways, providing mechanistic insight into its role in Parkinsons disease. Key resultsO_LICentrosome-linked LRRK2 network: BioID combined with co-evolutionary analysis identifies a highly conserved module enriched in centrosomal and microtubule-associated proteins, including CYLD as a top co-evolved interactor. C_LIO_LIConformation-specific interactions: AlphaFold-Multimer modelling reveals distinct classes of LRRK2 interactors that bind different domains and conformations ("locked" vs. "unlocked"), corresponding to specific cellular functions. C_LIO_LIState-dependent rewiring of the interactome: The type I inhibitor MLi-2 selectively redirects LRRK2 to centriolar satellite proteins, whereas RAB29 co-expression shifts LRRK2 interactions toward vesicular and lysosomal pathways. C_LI

neuroscience↗

Learning and actioning general principles of cancer cell drug sensitivity

High-throughput screening platforms for the profiling of drug sensitivity of hundreds of cancer cell lines (CCLs) have generated large datasets that hold the potential to unlock targeted, anti-tumor therapies. In this study, we leveraged these datasets to create predictive models of cancer cells drug sensitivity. To this aim we trained explainable machine learning algorithms by employing cell line transcriptomics to predict the growth inhibitory potential of drugs. We used large language models (LLMs) to expand descriptions of the mechanisms of action (MOA) for each drug starting from available annotations, which were matched to the semantically closest pathways from reference knowledge bases. By leveraging this AI-curated resource, and the interpretability of our model, we demonstrated that pathways enriched for genes crucial for prediction often matched known drug-MOAs and essential genes, suggesting that our models learned the molecular determinants of drug response. Furthermore, we demonstrated that by incorporating only LLM-curated genes associated with MOAs, we enhanced the predictive accuracy of our drug models. To enhance translatability to a clinical setting, we employed a pipeline to align bulk RNAseq from CCLs, used for training the models, to those from patient samples, used for inference. We proved the effectiveness of our approach on TCGA samples, where patients best scoring drugs matched those prescribed for their cancer type. We further showed its usefulness by predicting and experimentally validating effective drugs for the patients of two highly lethal solid tumors, i.e. pancreatic cancer and glioblastoma. In summary, our method facilitates the inference and interpretation of cancer cell line drug sensitivity and holds potential to effectively translate them into new cancer therapeutics. Highlights-Interpretable drug-response prediction models were trained on large scale pharmacogenomics data sets (i.e. GDSC and PRISM). -Large language models were used to enhance the curation of biological pathways associated to drugs MOA -Unbiased interpretation of the models demonstrated learning of drug MOAs and gene essentiality -Inference of TCGA cohort samples recovered mono- and combination cancer drug prescriptions and indicate potential repurposing candidates. -Drug candidates predicted from bulk RNAseq samples of pancreatic cancer and glioblastoma were experimentally validated.

bioinformatics↗