Biology subjects

Ceci, P.

Publications and source records attributed to Ceci, P..

3 recordsLinked to original sources

bioRxiv2025

Phylogenetics, evolution and biogeography of four Digitaria food crop lineages across West Africa, India, and Europe

Background and AimsMillet crops in the grass genus Digitaria include white and black fonio (D. exilis and D. iburua), raishan (D. compacta) and Polish millet (D. sanguinalis), cultivated across West Africa, India, and Europe. Fonio and raishan crops are important to supporting food security and subsistence agricultural systems in rural communities, while D. sanguinalis is no longer cultivated. These crops are resilient to challenging climates. We aim to produce an integrated study of these crops: a phylogeny of the Digitaria genus including all four food species, to identify key crop wild relatives (CWRs); time-calibrated biogeographic analysis, to investigate the history and evolution of Digitaria; and morphological study to assess the transition between wild and domesticated species. MethodsWe use the Angiosperm 353 target-enrichment sequencing approach to produce maximum likelihood and coalescent model nuclear phylogenies for 46 Digitaria species, including ploidy estimations, and bayesian methods to propose an evolutionary and biogeographic history for the genus. Morphology of wild and cultivated species is investigated for spikelets and growth habits using microscopy and SEM imaging techniques. Key ResultsFour distinct lineages are proposed for the evolution of Digitaria crops, and close CWRs D. fuscescens, D. atrofusca, D. setigera and D. radicosa, and D. ciliaris are identified. South and eastern Africa is proposed as the origin of early Digitaria divergence, with crop lineages diverging from wild relatives around 2-6mya. Incomplete domestication traits are observed, including the loss of trichomes, but no significant difference in spikelet or abscission zone morphology. ConclusionsDigitaria crops have important climate-resilient traits and hold strong potential for stabilising vulnerable food systems against the challenges of future climate change. The knowledge produced in this study about CWRs will be useful in improving crop traits through targeted breeding and indigenous crop conservation programmes.

genetics↗

bioRxiv2025

Impacts of climate change on fonio millet: in-vitro seed germination and suitability modelling of an important indigenous West African crop

Seed germination is highly temperature sensitive. Climate change factors such as increasing temperatures are likely to have a harmful effect on agriculture, particularly after crop sowing. Better utilisation of indigenous, arid-resilient crops like fonio (Digitaria exilis) are a commonly proposed solution to improving food security. This study develops knowledge of fonio germination requirements and how these correspond to future climate conditions across West Africa. We use a combined approach; integrating seed germination experiments under a range of temperatures, and niche suitability modelling to investigate how cultivation of fonio will be impacted by climate change. We find that from 37 seed accessions collected across Guinea, Togo, Mali, and Burkina Faso, the ceiling temperature for germination is around 42{degrees}C, with an optimum temperature of 30-35{degrees}C - also noted from phenotypic observations. Drought trials show successful germination to beyond -1MPa. There is no obvious difference in response by accessions originating from either hotter or cooler climates. By comparing these temperature thresholds with future climate predictions, alongside a suitability modelling approach, we predict an average decline of 10% in the suitable area for fonio cultivation, especially affecting Senegal, Mali, and Burkina Faso. Newly suitable area is predicted to increase in Guinea, Ghana, Cote dIvoire, and Nigeria by around 5%. These findings provide valuable insight for developing future dryland agriculture policies and prioritisation of resilient crops.

plant biology↗

bioRxiv2024

A circuit involving the lncRNA MB3 and the driver genes MYC and OTX2 inhibits apoptosis in Group 3 Medulloblastoma by regulating the TGF-β pathway via HMGN5

BackgroundGroup 3 (G3) is one of the most common, aggressive and fatal subtypes of the paediatric cerebellar tumour Medulloblastoma (MB), primarily driven by the MYC oncogene. Targeting MYC has long been challenging and this, combined with our incomplete understanding of G3 MB molecular bases, has hindered the development of effective targeted therapies. Long noncoding RNAs (lncRNAs), with their extensive oncogenic roles, cancer-specific expression, and connection to MYC biology, offer opportunities for unravelling this complexity and providing new insights and therapeutic targets. MethodologyUsing genome-wide, molecular and cellular assays, we characterised the activity of the MYC-dependent, anti-apoptotic lncRNA lncMB3 in G3 MB cells. ResultsThrough transcriptomic and interactomic analyses, we clarified lncMB3 function and mode-of-action. LncMB3 controls the TGF-{beta} pathway, critically altered in G3 medulloblastomagenesis. This regulation occurs via the direct coding-noncoding RNA interaction between lncMB3 and the mRNA for the epigenetic factor HMGN5, with both sharing targets in the TGF-{beta} cascade. This axis converges on apoptosis through OTX2, another G3 MB driver gene, and photoreceptor lineage genes. Synergistic effects between lncMB3 targeting and cisplatin treatment underscores the relevance of this regulatory network in vitro. Finally, we propose novel ferritin-based nanocarriers as efficient delivery tools for antisense oligonucleotides targeting lncMB3. ConclusionsLncMB3 emerges as a central node linking MYC amplification to apoptosis inhibition through a circuit involving RNA-based mechanisms, G3 MB key drivers and underexplored factors. This integrated framework deepens our understanding of G3 MB molecular underpinnings and lay the foundation for translating lncRNA research into potential applications.

cancer biology↗