Biology subjects

Coelho-Rato, L. S.

Publications and source records attributed to Coelho-Rato, L. S..

3 recordsLinked to original sources

bioRxiv2025

A Mass Spectrometry-Based Interactome Study on Anisomelic Acid and Its Effects on HPV16 E7

Human papillomavirus (HPV)-driven epithelial cancers rely on actions of viral oncoproteins, notably E7, which disrupts cell cycle control through inactivation of the tumor suppressor pRb. While prophylactic vaccines prevent infection, effective therapeutics for existing HPV-associated malignancies remain lacking. Here, we investigate the natural diterpenoid anisomelic acid (AA) and its mechanism of promoting HPV16 E7 degradation. Using cellular thermal shift assay (CETSA), we demonstrate that AA binds to E7, increasing its thermal stability and suggesting a direct molecular interaction. Mass spectrometry-based interactome analysis revealed that AA treatment reshapes the E7 interactome, enriching for E3 ubiquitin ligases (UBR4, TRIP12, TRIM28), the scaffold protein SQSTM1, and HSP40/HSP70 chaperone complexes involved in protein quality control and misfolded protein signaling. These data support a model in which AA binding induces conformational changes in E7 that enhance its recognition by ubiquitin-proteasome and chaperone-mediated degradation pathways. Our findings provide mechanistic insight into AAs antiviral mode of action and highlight its potential as a lead compound for targeted degradation of HPV oncoproteins.

cancer biology↗

bioRxiv2021

Cytoskeletal vimentin regulates cell size and autophagy through mTORC1 signaling

The nutrient-activated mTORC1 (mechanistic target of rapamycin kinase complex 1) signaling pathway determines cell size by controlling mRNA translation, ribosome biogenesis, protein synthesis, and autophagy. Here we show that vimentin, a cytoskeletal intermediate filament protein that we know to be important for wound healing and cancer progression, determines cell size through mTORC1 signaling, an effect that is also manifested at the organism level in mice. We found that vimentin maintains normal cell size by supporting mTORC1 activation and through inhibition of autophagic flux. This regulation is manifested at all levels of downstream target activation and regulation of protein synthesis. We show that vimentin controls mTORC1 mobility by allowing access to lysosomes. Vimentin inhibits the autophagic flux in normal fibroblasts even under starved conditions, indicating a growth factor-independent inhibition of autophagy at the level of mTORC1. Our findings demonstrate that vimentin couples cell size signaling and autophagy with the biomechanic, sensing, and kinetic functions of the cytoskeleton.

cell biology↗

bioRxiv2020

In vivo-mimicking 3D cultures secrete distinct extracellular vesicles upon cancer cell invasion

Extracellular vesicles (EVs) loaded with biomolecules are important in intercellular communication and mediate local and long-range signals in cancer metastasis. However, it is currently unknown how the development of the primary tumor and onset of invasion affect the secretion and characteristics of EVs. In this study, we developed an EV production method utilizing in vivo-mimicking extracellular matrix-based 3D cultures, which allows tracking of EVs over the course of invasive development of tumor organoids. Using this method, combined with proteomic profiling, we show that PC3 human prostate cancer organoids secrete EVs with previously undefined protein cargo, which substantially differs from EV cargo of 2D cultured cells. Intriguingly, an increase in EV amounts and extensive changes in EV protein composition were detected upon invasive transition of the organoids. These results reveal that EV secretion and cargo loading are highly dependent on the developmental status of the tumor organoid, emphasizing the necessity of in vivo-mimicking conditions for discovery of novel cancer-derived EV components, applicable as diagnostic markers for cancer.

cell biology↗