Publications by authors named "Nicolas Papon"

Monoterpene indole alkaloids (MIAs) are valuable metabolites produced in numerous medicinal plants from the Apocynaceae family such as Alstonia scholaris, which synthesizes strictamine, a MIA displaying neuropharmacological properties of a potential importance. To get insights into the MIA metabolism in A. scholaris, we studied here both the spatial and transcriptional regulations of MIA genes by performing a robust transcriptomics analysis of the main plant organs, leaf epidermis but also by sequencing RNA from leaves transiently overexpressing the master transcriptional regulator MYC2.

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Article Synopsis
  • Plant-specialized metabolism is a rich source of bioactive compounds, like monoterpene indole alkaloids (MIAs), known for their health benefits including anticancer and neuroactive properties.
  • The types of MIAs, particularly pachysiphine derivatives, have promising medical applications but are found in very low quantities in certain plant species, and there is a lack of genomic data needed to enhance their production.
  • This study presents the genome sequence of the toad tree (Tabernaemontana elegans) and identifies genes that can synthesize pachysiphine, leading to engineered MIAs in yeast, thus paving the way for better production of these valuable compounds for pharmaceutical use.
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  • Invasive fungal infections are a significant cause of death among patients who have undergone allogeneic hematopoietic stem cell transplants, even when they are on antimicrobial prophylaxis.
  • A new study by Zhai and colleagues highlights that heteroresistance, which is a form of resistance in fungi, contributes to the occurrence of Candida parapsilosis infections in these patients despite micafungin treatment.
  • The mechanisms behind these infections remain unclear, indicating a need for further research in this area.
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Two-component systems (TCSs) are diverse cell signaling pathways that play a significant role in coping with a wide range of environmental cues in both prokaryotic and eukaryotic organisms. These transduction circuitries are primarily governed by histidine kinases (HKs), which act as sensing proteins of a broad variety of stressors. To date, nineteen HK groups have been previously described in the fungal kingdom.

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Our knowledge of the biosynthesis of medicinal compounds from plants remains limited. A new study has deciphered the complete metabolic pathway leading to the biosynthesis of the psychedelic mescaline in the cactus peyote, suggesting the development of biotechnological strategies for a sustainable supply of this important plant drug.

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Plant bioactives hold immense potential in the medicine and food industry. The recent advancements in omics applied in deciphering specialized metabolic pathways underscore the importance of high-quality genome releases and the wealth of data in metabolomics and transcriptomics. While harnessing data, whether integrated or standalone, has proven successful in unveiling plant natural product (PNP) biosynthetic pathways, the democratization of machine learning in biology opens exciting new opportunities for enhancing the exploration of these pathways.

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Invasive fungal infections represent millions of deaths per year, but their pathophysiology remains insufficiently understood. Host-fungi interplay has been recently shown to include extracellular vesicles derived from fungi and host infected cells. In this forum article we discuss their emerging role in modulating the host immune response with particular emphasis on their regulatory involvement during Candida albicans infection.

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Transplant patients, including solid-organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients, are exposed to various types of complications, particularly rejection. To prevent these outcomes, transplant recipients commonly receive long-term immunosuppressive regimens that in turn make them more susceptible to a wide array of infectious diseases, notably those caused by opportunistic pathogens. Among these, invasive fungal infections (IFIs) remain a major cause of mortality and morbidity in both SOT and HSCT recipients.

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Specialized metabolites possess diverse interesting biological activities and some cardenolides- and monoterpene indole alkaloids- (MIAs) derived pharmaceuticals are currently used to treat human diseases such as cancers or hypertension. While these two families of biocompounds are produced by specific subfamilies of , one member of this medicinal plant family, the succulent tree Drake (also known as Madagascar palm), does not produce such specialized metabolites. To explore the evolutionary paths that have led to the emergence and loss of cardenolide and MIA biosynthesis in , we sequenced and assembled the genome by combining Oxford Nanopore Technologies long-reads and Illumina short-reads.

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Natural products represent an inestimable source of valuable compounds for human health. Notably, those produced by plants remain challenging to access due to their low production. Potential shortages of plant-derived biopharmaceuticals caused by climate change or pandemics also regularly tense the market trends.

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Monoterpene indole alkaloids (MIAs) are a structurally diverse family of specialized metabolites mainly produced in Gentianales to cope with environmental challenges. Due to their pharmacological properties, the biosynthetic modalities of several MIA types have been elucidated but not that of the yohimbanes. Here, we combine metabolomics, proteomics, transcriptomics and genome sequencing of Rauvolfia tetraphylla with machine learning to discover the unexpected multiple actors of this natural product synthesis.

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  • Signals play a crucial role in the arbuscular mycorrhizal (AM) symbiosis between fungi and plants, with root-exuded strigolactones recognized as key early cues, while the involvement of other phytohormones like ethylene and cytokinins is less explored.
  • The study identified that an ethylene receptor, RiHHK6, in AM fungi can effectively sense ethylene signals and enhance spore germination in response to certain cytokinins, suggesting the fungi's adaptability to these hormonal cues.
  • The contrasting behavior of a candidate cytokinin receptor, RiHHK7, indicates that the perception of cytokinins might involve different receptors, highlighting the diverse roles of phytoh
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Fungal infections caused by Scedosporium species are rising among immunocompromised and immunocompetent patients. Within the immunocompetent group, patients with cystic fibrosis (pwCF) are at high risk of developing a chronic airway colonization by these molds. While S.

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  • * Lebanon's ongoing economic crisis has affected access to medical care, leading to increased antifungal drug prices, making the situation more critical as the impact of antifungal resistance remains poorly understood.
  • * A survey identified 15 studies from 1998 to 2023, highlighting a predominant focus on candidiasis, increased infections in hospitals during the COVID-19 pandemic, and a need for better diagnostics and antifungal stewardship programs to combat resistance effectively.
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Toxicants such as smoke, biofuel, and pollutants constantly challenge our respiratory health, but little is known about the pathophysiological processes involved. In a new report, Lin et al. provide evidence that our bacterial and fungal lung populations orchestrate the interplay between environmental exposure and lung functions, thereby conditioning health outcomes.

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Elucidating biosynthetic pathways of plant specialized metabolites is a tricky but essential task for the biotechnological production of plant drugs. In a new report, Li et al. used a single-cell multi-omics approach to provide an integrative view of the architecture and regulation of anticancer alkaloid routes in Madagascar periwinkle.

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Cocaine and hyoscyamine are two tropane alkaloids (TA) from Erythroxylaceae and Solanaceae, respectively. These famous compounds possess anticholinergic properties that can be used to treat neuromuscular disorders. While the hyoscyamine biosynthetic pathway has been fully elucidated allowing its de novo synthesis in yeast, the cocaine pathway remained only partially elucidated.

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Synthetic biology is constantly making progress for producing compounds on demand. Recently, Yocum and collaborators have developed an outstanding approach based on the anchoring of biosynthetic enzymes to the peroxisomal membrane. This allowed access to an untapped resource of acetyl-CoA and stimulated the synthesis of a valuable polyketide.

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