Biology subjects

Gouveia, L.

Publications and source records attributed to Gouveia, L..

4 recordsLinked to original sources

bioRxiv2026

A pan-cancer single-cell atlas of pericytes

Pericytes display marked tissue-specific transcriptional identities, raising the question of whether tumour-associated pericytes converge towards shared adaptive states across cancers. Here, we built a pan-cancer single-cell RNA sequencing atlas of pericytes, integrating nearly four million cells across nine tissues, complemented by spatial transcriptomic analyses. Despite their physiological diversity, pericytes were recurrently expanded in tumours and converged on a common transcriptional program, the tumour-associated pericyte signature (TAPS). TAPS robustly identified pericytes across datasets, outperforming canonical markers in tumour contexts. Tumour-associated pericytes further diversified into specialised states including extracellular matrix (ECM)-associated and interferon (IFN)-responsive programs, which occupy mutually exclusive tumour ecosystems. ECM-associated pericytes were enriched in desmoplastic, fibroblast-rich regions and were associated with adverse clinical outcomes across multiple cancer types. IFN-responsive pericytes accumulated in inflammatory niches, with macrophages implicated as candidate drivers of specialisation. Together, our multi-layered analysis defines convergent and specialised tumour-associated pericyte programs across human cancers.

cancer biology↗

bioRxiv2025

Context-dependent response of endothelial cells to PIK3CA mutation

Cancer mutations in the PIK3CA gene cause congenital disorders. The endothelium is among the most frequently affected tissues in these disorders, displaying aberrant vascular overgrowth in the form of malformations. Pathological PIK3CA vascular phenotypes are found in veins and capillaries but rarely in arteries for reasons that are unclear at present. Here, using lineage tracing, we show that expression of mutated PIK3CAH1047R in endothelial cells leads to marked clonal expansions in capillary and venous endothelial cells. In contrast, mature arterial endothelial cells are refractory to PIK3CA mutation under these conditions and never display pathological phenotypes. Moreover, PIK3CAH1047Rexpression in arterial precursors interrupts arterial differentiation, thereby driving fate switch towards venous identity. This fate rewiring offers an additional layer of protection to prevent arterial damage in response to PIK3CA genetic perturbation. Molecularly, the PIK3CAH1047R-driven arterial-to-venous fate switch is orchestrated by upregulation of the vein-specifying transcription factor Nr2f2/COUP-TFII. Our findings reveal that pathogenic responses to PIK3CAH1047Rgreatly depend on the diferentation stage and fate trajectory of the targeted cell. Arteries are thus shielded against PIK3CA mutation, solving the long-standing question on the rarity of PIK3CA-related arterial malformations observed in patients.

developmental biology↗

bioRxiv2024

Growth characterization and biostimulant potential of Coelastrella sp. D14 a greenmicroalga isolated from a solar panel.

Extremophile environments are an important source for finding microorganisms with a potential for biotechnological applications. Among these microorganisms, microalgae contribute to several sustainable processes such as wastewater treatments or nutrition. In this work it was characterized a microalga isolated from a solar panel. The morphological and phylogenetic analysis revealed that the isolate collected was a Coelastrella strain. Cultivation and stress experiments has shown that Coelastrella sp. D14 can resist a long period of desiccation and it can grow on cheap sources such as piggery wastewaters (PWW). This work reports that a Coelastrella strain displays biostimulant properties with a germination index of 123% on Lepidium sativum when D14 biomass grown at 10% piggery effluent was used. Altogether, these results suggest that this novel strain could be a good chassis for further biotechnological applications. HighlightsO_LICoelastrella sp. D14, a xero-tolerant strain, has been isolated from a solar panel C_LIO_LIThis strain can grow on piggery wastewater C_LIO_LICoelastrella sp. D14 can promote germination of Lepidium sativum C_LI

microbiology↗

bioRxiv2018

Individual based genetic analyses support asexual hydrochory dispersal in Zostera noltei

Dispersal beyond the local patch in clonal plants was typically thought to result from sexual reproduction via seed dispersal. However, evidence for the separation, transport by water, and re-establishment of asexual propagules (asexual hydrochory) is mounting suggesting other important means of dispersal in aquatic plants. Using an unprecedented sampling size and microsatellite genetic identification, we describe the distribution of seagrass clones along tens of km within a coastal lagoon in Southern Portugal. Our spatially explicit individual-based sampling design covered 84 km2 and collected 3 185 Zostera noltei ramets from 803 sites. We estimated clone age, assuming rhizome elongation as the only mechanism of clone spread, and contrasted it with paleo-oceanographic sea level change. We also studied the association between a source of disturbance and the location of large clones. A total of 16 clones were sampled more than 10 times and the most abundant one was sampled 59 times. The largest distance between two samples from the same clone was 26.4 km and a total of 58 and 10 clones were sampled across more than 2 and 10 km, respectively. The number of extremely large clone sizes, and their old ages when assuming the rhizome elongation as the single causal mechanism, suggests other processes are behind the span of these clones. We discuss how the dispersal of vegetative fragments in a stepping-stone manner might have produced this pattern. We found higher probabilities to sample large clones away from the lagoon inlet, considered a source of disturbance. This study corroborates previous experiments on the success of transport and re-establishment of asexual fragments and supports the hypothesis that asexual hydrochory is responsible for the extent of these clones.

ecology↗