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Spadafora, C.

Publications and source records attributed to Spadafora, C..

2 recordsLinked to original sources

From Proteome Mining to Structural Validation: Phosphopyruvate Hydratase as a Structurally Tractable Drug Target in Kinetoplastid Parasites

Chagas disease, caused by Trypanosoma cruzi, demands novel therapeutic strategies that overcome the toxicity and limited efficacy of current treatments. To address this need, herein we report an integrative, target-centric strategy that combines parasite proteome mining, structural modeling, and experimental validation. Functional enrichment and druggability analyses identified phosphopyruvate hydratase (PPH) as a promising candidate due to its essential metabolic role and limited similarity to human homologs. Notably, proteome mining revealed the presence and conservation of PPH across kinetoplastid parasites, including Leishmania donovani, supporting its evaluation beyond T. cruzi. For the selected PPH sequences, AlphaFold-derived three-dimensional models underwent extensive molecular dynamics refinement, yielding stable conformational ensembles suitable for structure-based studies. Using this validated model, virtual screening of the Latin American Natural Products Database - LANaPDB - identified aptosimon as a top-ranked compound candidate. Molecular dynamics simulations further showed ligand-dependent binding behavior, suggesting alternative binding modes distinct from the canonical substrate configuration. In vitro assays demonstrated consistent antiparasitic activity against intracellular T. cruzi amastigotes (IC = 3.52 {+/-} 0.023 {micro}g/mL) and Leishmania donovani promastigotes (IC = 13.06 {+/-} 0.018 {micro}g/mL), supporting the biological relevance of the aptosimon-related lignan chemotype, hinokinin, across two kinetoplastid parasite models. Together, these results support PPH as a structurally tractable and biologically relevant candidate target, while identifying an aptosimon-related lignan chemotype, represented experimentally by hinokinin, as a cross-species antiparasitic scaffold that warrants further biochemical target-validation studies.

bioinformatics↗

Reverse transcriptase inhibitors induce autophagy in a LINE-1 ORF1p-dependent manner

Human Long Interspersed Nuclear Element-1 (LINE-1) retrotransposons propagate throughout the genome via reverse-transcribed RNA intermediates. LINE-1 expression is pervasive in cancer. Functional LINE-1s encode two proteins: ORF1p, an RNA-binding protein, and ORF2p, harboring reverse transcriptase and endonuclease activities. Reverse transcriptase inhibitors, including non-nucleoside (NNRTI) and nucleoside (NRTI) inhibitors, inhibit cancer cell proliferation and antagonize cancer progression. We previously found that two NNRTIs induced DNA damage, nuclear lamin rupture, micronuclei formation, and autophagy in prostate cancer cells. We now find that two different RTIs up-regulate LINE-1 mRNA expression and ORF1p abundance in nuclei, triggering ORF1p interactions with lamin B1 and with DNA damage factors. ORF1p accumulates within micronuclei with damaged DNA and with the autophagy receptor p62. We further demonstrate that inhibiting autophagy, or decreasing ORF1p levels, prevent DNA damage and preserve lamin B1 integrity, uncoverig a role of LINE-1-ORF1p in the autophagy response of cancer cells, independent on retrotranscription events.

cell biology↗