Comptes Rendus Biologies最新文献

Parkinson’s disease (PD) is a multifactorial disorder involving various biological pathways. However, it is more accurate not to define PD as a unique entity, but rather as a mixture of several diseases with similar phenotypes. Attempts to classify subtypes of PD based on the clinical phenotype or biomarkers were tried. Nonetheless, for a subset of individuals, the classification based on the implied gene appears to be the most practical. Although the SNCA gene was the first identified in rare patients, pathogenic variants in GBA1 and LRRK2 are the most common genetic causes or risk factors of PD, and PRKN is the most frequent gene of autosomal recessive PD. Patients with pathogenic variants in SNCA, GBA1, LRRK2 or PRKN show various clinical, anatomopathological and biochemical aspects. Therefore, these four genes associated to PD are of particular interest for the development of targeted therapies. This fact is reinforced by the reality that current approaches are only symptomatic, and no curative treatment is available today. A number of clinical trials aiming to slow or stop disease progression are running, based on the gene involved. In this review, we will discuss the therapeutic approaches targeting SNCA, GBA1, LRRK2 and PRKN.

A major facet of the Anthropocene is global change, such as climate change, caused by human activities, which drastically affect biodiversity with all-scale declines and homogenization of biotas. This crisis does not only affect the ecological dynamics of biodiversity, but also its evolutionary dynamics, including genetic diversity, an aspect that is generally neglected. My tenet is therefore to consider biodiversity dynamics from an eco-evolutionary perspective, i.e. explicitly accounting for the possibility of rapid evolution and its feedback on ecological processes and the environment. I represent the impact of the various avatars of global change in a temporal perspective, from pre-industrial time to the near future, allowing to visualize their dynamics and to set desired values that should not be trespassed for a given time (e.g., +2 °C for 50 years from now). After presenting the impact of various stressors (e.g., climate change) on biodiversity, this representation is used to heuristically show the relevance of an eco-evolutionary perspective: (i) to analyze how biodiversity will respond to the stressors, for example by seeking out more suitable conditions or adapting to new conditions; (ii) to serve in predictive exercises to envision future dynamics (decades to centuries) under stressor impact; (iii) to propose nature-based solutions to the crisis. Significant obstacles stand in the way of the development of such an approach, in particular the general lack of interest in intraspecific diversity, and perhaps more generally a lack of understanding that, we, humans, are only a modest part of biodiversity.

In the mammalian central nervous system (CNS), adult neurons fail to regenerate spontaneously upon axon injury, which leads to a permanent and irreversible loss of neuronal functions. For more than 15 years, much effort was invested to unlock axon regrowth programs based on extensive transcriptomic characterization. However, it is now well described that mRNA and protein levels correlate only partially in cells, and that the transcription process (from DNA to mRNA) may not directly reflect protein expression. Conversely, the translation process (from mRNA to protein) provides an additional layer of gene regulation. This aspect has been overlooked in CNS regeneration. In this review, we discuss the limitations of transcriptomic approaches to promote CNS regeneration and we provide the rationale to investigate translational regulation in this context, and notably the regulatory role of the translational complex. Finally, we summarize our and others’ recent findings showing how variations in the translational complex composition regulate selective (mRNA-specific) translation, thereby controlling CNS axon regrowth.

Recent climate and land use change, and pollution have led to concerning alterations in biodiversity and ecosystem functions, jeopardizing nature’s contributions to people. Mountainous regions are not immune to these threats, experiencing the impacts of global warming, increased recreational activities, and changes in agricultural practices. Leveraging the natural elevational gradients of mountain environments, the ORCHAMP program was established in 2016 as a comprehensive initiative to monitor, understand, and predict the repercussions of environmental changes on biodiversity and associated ecosystem functions in the French Alps and Pyrenees.Beyond its monitoring role, ORCHAMP has catalyzed the development of tools for data integration, statistical analyses, visualization, and AI-based automated data processing and predictions. Through a combination of traditional sampling methods (e.g., botanical surveys) and cutting-edge technologies (remote-sensing, environmental DNA, video, and acoustic sensors), the program offers a holistic approach to understanding how biodiversity faces environmental changes. By showcasing examples and key results, this paper provides an overview of ORCHAMP’s advancements and outlines potential future directions. The broad inclusion of diverse monitoring techniques and data treatments positions ORCHAMP as a pioneering effort, paving the way for long-term insights into biodiversity dynamics—a crucial step toward effective conservation strategies.

Biosecurity is a word including, in French, two concepts which are differently expressed in the English literature: the biosafety (to prevent accidental releases of infectious agents, for example, in research laboratories) and the biosecurity (to prevent the voluntary dispersion of infectious agents by bioterrorists, for example). Up to now, bioterrorism using a biological weapon has been very rare. Epidemiological surveillance is frequently seen as an efficient tool to achieve a better biosafety, and increase biosecurity. However, biosecurity requires an alert system. Traditional surveillance, which was developed to help to design the health policies, lacks the sensitivity and rapid response delay necessary for alert. Biology brings new opportunities for alert and surveillance. Examples are the monitoring of sewer systems and the development of CRISPR tools for detection of biological agents. A new problem is that these tools can be used out of the research laboratories, because they are relatively cheap and easy to develop. Finally, whatever the method used to identify quickly a new hazard, the key problem is the “preparedness” to identify and connect quickly the biomedical experts able to provide the best response to this hazard.

The use of nanotechnologies for the encapsulation of pharmacologically active molecules (nanomedicines) has enhanced the delivery of these molecules within the body after administration. By releasing the active ingredient at the level of pathological cells and tissues, these nanocarriers help reduce toxicity while improving therapeutic efficacy. They also protect fragile molecules from rapid metabolization and can promote their intracellular penetration. Nanomedicines have made significant advances in various therapeutic areas such as oncology, infectious diseases, and several neurological disorders. They have also contributed to groundbreaking discoveries, including the introduction of the first mRNA vaccine (against COVID-19), and have improved certain imaging and diagnostic techniques, too. Depending on the country and therapeutic indications, between 40 to 60 nanomedicines are currently on the market, with over a hundred in clinical trials. This review aims to describe and discuss the characteristics and functionalities of the different generations of nanocarriers, from their inception to the present day, discussing the prospects they offer for the production of therapeutic proteins, for facilitating gene editing (CRISPR/Cas9), and for enabling immune checkpoint blockade in oncology. The potential of extracellular vesicles and exosomes as drug carriers is also explored. These advances compel researchers to consider the dual risks, both conscious and unconscious, that they may pose.

Neurogenesis is a lifelong process, generating neurons in the right amount, time and place and with the correct identity to permit the growth, function, plasticity and repair of the nervous system, notably the brain. Neurogenesis originates from neural progenitor cells (NPs), endowed with the capacity to divide, renew to maintain the progenitor population, or commit to engage in the neurogenesis process. In the adult brain, these progenitors are classically called neural stem cells (NSCs). We review here the commonalities and differences between NPs and NSCs, in their cellular and molecular attributes but also in their potential, regulators and lineage, in the embryonic and adult brains. Our comparison is based on the two most studied model systems, namely the telencephalon of the zebrafish and mouse. We also discuss how the population of embryonic NPs gives rise to adult NSCs, and outstanding questions pertaining to this transition.

Ever since the term “biodiversity” was first defined, it has been used in a mixed way, referring on the one hand to the characterisation of living organisms (which is the domain of systematics), and on the other hand to their functional interactions (which are the domain of ecology). This ambiguity has led to the terms biodiversity and ecosystem being used almost synonymously, a mistake that is both epistemologically and politically damaging. To clear up this confusion, the term biodiversity should be reserved for what we observe when we characterise or discover “what there is” (a task for systematics) at the three infra-specific, specific and supra-specific levels, and the term ecosystem should be reserved for what we observe when we are interested in the functional interactions (“what it does”, a task for ecology) between living organisms, and between the latter and the abiotic environment.

Cancer is a biological process that emerged at the end of the Precambrian era with the rise of multicellular organisms. Traditionally, cancer has been viewed primarily as a disease relevant to human and domesticated animal health, attracting attention mainly from oncologists. In recent years, however, the community of ecologists and evolutionary biologists has recognized the pivotal role of cancer-related issues in the evolutionary paths of various species, influencing multiple facets of their biology. It has become evident that overlooking these issues is untenable for a comprehensive understanding of species evolution and ecosystem functioning. In this article, we highlight some significant advancements in this field, also underscoring the pressing need to consider reciprocal interactions not only between cancer cells and their hosts but also with all entities comprising the holobiont. This reflection gains particular relevance as ecosystems face increasing pollution from mutagenic substances, resulting in a resurgence of cancer cases in wildlife.

The association of maize (Zea mays ssp. mays), common bean (Phaseolus vulgaris), and squash (Cucurbita ssp.) within the milpa represents the most emblematic multi-cropping subsistence system of Mesoamerica. This system was likely established in the Guerrero-Jalisco area in southwestern Central Mexico shortly after—or perhaps even before—the domestication of the three taxa. Its success relies on several factors: complementarity of nutritional intakes, resilience to biotic and abiotic constraints, and the mobilization of positive interactions between the three taxa, enabling the system to be productive under input-limited conditions. Higher yields compared to sole-cropping have frequently been described and attributed to the complementarity between the aerial and root systems of the different taxa of the milpa, as well as to direct and indirect facilitation processes involving root exudates, bacterial symbioses, and the mycorrhizal network. In Europe, while practiced until recently, the milpa has gradually been abandoned in favor of maize sole-cropping, except in some isolated regions (such as Transylvania) where this traditional agricultural system has persisted. The question of whether varieties of the three taxa used in multi-cropping systems were co-introduced to Europe at the time of the discovery of the Americas, as opposed to being re-associated later in Europe, remains open. It is important to note that maize usage differed: maize of flint type is coarsely ground for the preparation of polenta in Europe, while in Mesoamerica, tropical varieties are soaked in alkaline solution to improve nutritional quality before being finely ground to make tortilla dough. Recently, maize-bean intercropping has been reintroduced into modern European agricultural systems. However, the use of elite varieties and chemical inputs in conventional conducts prevents full exploitation of positive interactions between species. We argue here that milpa has an important role to play in the agroecological transition. In this context, we propose avenues for the selection of varieties that promote synergies between species and discuss the constraints linked to its mechanization.