RESUMO
Decades of research have sought to determine the intrinsic and extrinsic mechanisms underpinning the regulation of neural progenitor maintenance and differentiation. A series of precise temporal transitions within progenitor cell populations generates all the appropriate neural cell types while maintaining a pool of self-renewing progenitors throughout embryogenesis. Recent technological advances have enabled us to gain new insights at the single-cell level, revealing an interplay between metabolic state and developmental progression that impacts the timing of proliferation and neurogenesis. This can have long-term consequences for the developing brain's neuronal specification, maturation state, and organization. Furthermore, these studies have highlighted the need to reassess the instructive role of glucose metabolism in determining progenitor cell division, differentiation, and fate. This review focuses on glucose metabolism (glycolysis) in cortical progenitor cells and the emerging focus on glycolysis during neurogenic transitions. Furthermore, we discuss how the field can learn from other biological systems to improve our understanding of the spatial and temporal changes in glycolysis in progenitors and evaluate functional neurological outcomes.
Assuntos
Glucose , Neurônios , Neurônios/metabolismo , Diferenciação Celular/fisiologia , Glucose/metabolismo , Biologia , EncéfaloRESUMO
Histones are subject to a diverse array of post-translational modifications. Among them, lysine acetylation is not only the most pervasive and dynamic modification but also highly consequential for regulating gene transcription. Although enzymes responsible for the addition and removal of acetyl groups were discovered almost 30 years ago, high-resolution structures of the enzymes in the context of their native complexes are only now beginning to become available, thanks to revolutionary technologies in protein structure determination and prediction. Here, we will review our current understanding of the molecular mechanisms of acetylation and deacetylation engendered by chromatin-modifying complexes, compare and contrast shared features, and discuss some of the pressing questions for future studies.
Assuntos
Histonas , Processamento de Proteína Pós-Traducional , Histonas/metabolismo , Acetilação , BiologiaRESUMO
Production, extraction, purification, and stabilization of integral membrane proteins are key steps for successful structural biology studies, in particular for X-ray crystallography or single particle microscopy. Here, we present the purification protocol of CntI from Pseudomonas aeruginosa, a new metallophore exporter of the Drug Metabolite Transporter (DMT) family involved in pseudopaline secretion. Subsequent to CntI purification, we optimized the buffer pH, salts, and additives by differential scanning fluorimetry (DSF), also known as Thermofluor Assay (TFA) or fluorescent thermal stability assay (FTSA), with the use of dye 1-AnilinoNaphthalene-8-Sulfonic acid (ANS), a fluorescent molecule compatible with detergents. After the buffer optimization, the purified CntI was analyzed by Size Exclusion Chromatography coupled with Multi-Angle Laser Light Scattering (SEC-MALLS), UV absorbance, and Refractive Index detectors, in order to determine the absolute molar mass of the protein-detergent complex, the detergent amount bound to the protein and the amount of protein-free detergent micelles. Altogether, these biophysical techniques give preliminary and mandatory information about the suitability of the purified membrane protein for further biophysical or structural investigations.
Assuntos
Detergentes , Proteínas de Membrana , Pseudomonas aeruginosa , Proteínas de Membrana Transportadoras , BiologiaRESUMO
Title: L'actualité scientifique vue par les étudiants du Master Biologie-Santé de l'université de Montpellier. Abstract: L'unité d'enseignement « Immunopathologie ¼ qui propose les brèves présentées dans ce numéro est suivie par des étudiants de divers parcours du Master Biologie Santé de l'université de Montpellier. Ce Master rassemble des étudiants issus du domaine des sciences et technologies et de domaines de la santé. On y étudie les bases physiopathologiques des maladies immunologiques, les cibles thérapeutiques et les mécanismes d'échappement des microorganismes et des tumeurs Les articles présentés ont été choisis par les étudiants selon leur domaine de prédilection.
Assuntos
Biologia , Estudantes , Humanos , UniversidadesRESUMO
General education in biological courses such as "Principal Biology" is an essential avenue for gaining an understanding of life science and developing an interest in the field. The reform of biological education teaching mode based on interdisciplinary approaches aims to foster cross-disciplinary talents, which is crucial for the rapid development of China's bioeconomy. Teaching method that simply superimposes different subjects is difficult to discover the value of interdisciplinary education. To address this, a novel teaching system and an innovative teaching mode were proposed for "Principal Biology" course by integrating science and engineering subjects, based on the cross-disciplinary feature in Beijing Institute of Technology. The system involves the design of cross-disciplinary course content and the integration of multiple disciplines and knowledge points based on students' majors, taking into account the characteristics of students' physical and mental development. To improve students' scientific literacy and interdisciplinary thinking ability, differentiated and major-driven teaching modes were applied by incorporating the "1+N" mixed and immersive cross-thinking training. The effectiveness of tailored cross-disciplinary teaching was evaluated using "in-teaching" and "post-teaching" data feedback models, which promote the optimization of teaching process and enhance the quality of education in cross-disciplinary biological science.
Assuntos
Disciplinas das Ciências Biológicas , Estudantes , Humanos , Currículo , Disciplinas das Ciências Biológicas/educação , Universidades , Biologia/educaçãoRESUMO
Abstract: This scholarly article delves into the multifaceted domains of human cloning, encompassing its biological underpinnings, ethical dimensions, and broader societal implications. The exposition commences with a succinct historical and contextual overview of human cloning, segueing into an in-depth exploration of its biological intri-cacies. Central to this biological scrutiny is a comprehensive analysis of somatic cell nuclear transfer (SCNT) and its assorted iterations. The accomplishments and discoveries in cloning technology, such as successful animal cloning operations and advances in the efficiency and viability of cloned embryos, are reviewed. Future improvements, such as reprogramming procedures and gene editing technology, are also discussed. The discourse extends to ethical quandaries intrinsic to human cloning, entailing an extensive contemplation of values such as human dignity, autonomy, and safety. Furthermore, the ramifications of human cloning on a societal plane are subjected to scrutiny, with a dedicated emphasis on ramifications encompassing personal identity, kinship connections, and the fundamental notion of maternity. Culminating the analysis is a reiteration of the imperative to develop and govern human cloning technology judiciously and conscientiously. Finally, it discusses several ethical and practical issues, such as safety concerns, the possibility of exploitation, and the erosion of human dignity, and emphasizes the significance of carefully considering these issues.
Assuntos
Clonagem de Organismos , Técnicas de Transferência Nuclear , Animais , Feminino , Humanos , Gravidez , Autoimagem , BiologiaRESUMO
It is well established that cells, tissues, and organisms exposed to low doses of ionizing radiation can induce effects in non-irradiated neighbors (non-targeted effects or NTE), but the mechanisms remain unclear. This is especially true of the initial steps leading to the release of signaling molecules contained in exosomes. Voltage-gated ion channels, photon emissions, and calcium fluxes are all involved but the precise sequence of events is not yet known. We identified what may be a quantum entanglement type of effect and this prompted us to consider whether aspects of quantum biology such as tunneling and entanglement may underlie the initial events leading to NTE. We review the field where it may be relevant to ionizing radiation processes. These include NTE, low-dose hyper-radiosensitivity, hormesis, and the adaptive response. Finally, we present a possible quantum biological-based model for NTE.
Assuntos
Efeito Espectador , Transdução de Sinais , Efeito Espectador/efeitos da radiação , Tolerância a Radiação , Radiação Ionizante , BiologiaRESUMO
In this paper, we propose and study several inverse problems of identifying/determining unknown coefficients for a class of coupled PDE systems by measuring the average flux data on part of the underlying boundary. In these coupled systems, we mainly consider the non-negative solutions of the coupled equations, which are consistent with realistic settings in biology and ecology. There are several salient features of our inverse problem study: the drastic reduction of the measurement/observation data due to averaging effects, the nonlinear coupling of multiple equations, and the non-negative constraints on the solutions, which pose significant challenges to the inverse problems. We develop a new and effective scheme to tackle the inverse problems and achieve unique identifiability results by properly controlling the injection of different source terms to obtain multiple sets of mean flux data. The approach relies on certain monotonicity properties which are related to the intrinsic structures of the coupled PDE system. We also connect our study to biological applications of practical interest.
Assuntos
Biologia , Ecologia , MatemáticaRESUMO
BACKGROUND: The presence of an outer shell has been recently described as a common feature of acute ischemic stroke (AIS) thrombi. We performed a systematic review of the current literature on shell genesis, structure, and clinical significance. METHODS: Following PRISMA guidelines, we searched Ovid Cochrane Central Register of Controlled Trials, Embase, Medline, Scopus, and Web of Science for studies reporting the composition and structure of AIS thrombi and clot analogs. Identified studies were added to Covidence software for primary screening. Two reviewers independently screened titles and abstracts followed by full-text screening. RESULTS: From 1290 identified studies, 10 were included in this review. Studies using histology/immunohistochemistry/immunofluorescence described fibrin, platelets, von Willebrand factor, and neutrophil extracellular traps as the main components of the shell. Scanning electron microscopy demonstrated a dense, compact fibrin/platelet-rich shell, and a core rich in polyhedrocytes. Microfluidics studies identified highly activated P-selectin-positive platelets and fibrin forming the core while secondary agonists adenosine diphosphate and thromboxane, along with loosely packed P-selectin-negative platelets constituted the shell. CONCLUSIONS: The composition, compaction, and integrity of the shell may impact thrombolysis and revascularization outcomes. The preponderance of studies supported this conclusion.
Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Trombose , Humanos , Selectina-P , Fibrina , BiologiaRESUMO
Proteolysis targeting chimeras (PROTACs) are heterobifunctional molecules that co-opt the cell's natural proteasomal degradation mechanisms to degrade undesired proteins. A challenge associated with PROTACs is the time and resource-intensive optimization; thus, the development of high-throughput platforms for their synthesis and biological evaluation is required. In this study, we establish an ultra-high-throughput experimentation (ultraHTE) platform for PROTAC synthesis, followed by direct addition of the crude reaction mixtures to cellular degradation assays without any purification. This 'direct-to-biology' (D2B) approach was validated and then exemplified in a medicinal chemistry campaign to identify novel BRD4 PROTACs. Using the D2B platform, the synthesis of 650 PROTACs was carried out in a 1536-well plate, and subsequent biological evaluation was performed by a single scientist in less than 1 month. Due to its ability to hugely accelerate the optimization of new degraders, we anticipate our platform will transform the synthesis and testing of PROTACs.
Assuntos
Proteínas Nucleares , Quimera de Direcionamento de Proteólise , Fatores de Transcrição , Bioensaio , Biologia , Proteólise , Ubiquitina-Proteína LigasesRESUMO
Carnivorous plants (approximately 850 species) are specific mixotrophic plants which all perform photosynthesis but need mainly nitrogen and phosphorous from animal or protist bodies [...].
Assuntos
Planta Carnívora , Nitrogênio , Animais , Fotossíntese/genética , Plantas/genética , BiologiaAssuntos
Neoplasias , Transcriptoma , Humanos , Biologia , Neoplasias/genética , Perfilação da Expressão GênicaRESUMO
Iron serves a critical role in many metabolic processes, including oxygen delivery (e.g., hemoglobin) and oxygen utilization for the generation of ATP (e.g., cytochromes). Disorders of iron metabolism are best recognized and evaluated in the context of iron's absorption, transportation, monitoring, cellular uptake, and recycling. This review highlights these processes so that disorders of iron deficiency and iron excess can be better understood. Key players in iron metabolism will be highlighted, such as hepcidin, ferroportin, erythroferrone, transferrin, ferritin, HFE, and the transferrin receptors.
Assuntos
Sobrecarga de Ferro , Ferro , Humanos , Ferro/metabolismo , Hepcidinas , Transferrina , Receptores da Transferrina/metabolismo , Oxigênio/metabolismo , BiologiaRESUMO
The potential for basic research to uncover the inner workings of regenerative processes and produce meaningful medical therapies has inspired scientists, clinicians, and patients for hundreds of years. Decades of studies using a handful of highly regenerative model organisms have significantly advanced our knowledge of key cell types and molecular pathways involved in regeneration. However, many questions remain about how regenerative processes unfold in regeneration-competent species, how they are curtailed in non-regenerative organisms, and how they might be induced (or restored) in humans. Recent technological advances in genomics, molecular biology, computer science, bioengineering, and stem cell research hold promise to collectively provide new experimental evidence for how different organisms accomplish the process of regeneration. In theory, this new evidence should inform the design of new clinical approaches for regenerative medicine. A deeper understanding of how tissues and organs regenerate will also undoubtedly impact many adjacent scientific fields. To best apply and adapt these new technologies in ways that break long-standing barriers and answer critical questions about regeneration, we must combine the deep knowledge of developmental and evolutionary biologists with the hard-earned expertise of scientists in mechanistic and technical fields. To this end, this perspective is based on conversations from a workshop we organized at the Banbury Center, during which a diverse cross-section of the regeneration research community and experts in various technologies discussed enduring questions in regenerative biology. Here, we share the questions this group identified as significant and unanswered, i.e., known unknowns. We also describe the obstacles limiting our progress in answering these questions and how expanding the number and diversity of organisms used in regeneration research is essential for deepening our understanding of regenerative capacity. Finally, we propose that investigating these problems collaboratively across a diverse network of researchers has the potential to advance our field and produce unexpected insights into important questions in related areas of biology and medicine.
Assuntos
Regeneração , Medicina Regenerativa , Humanos , BiologiaRESUMO
The TEM8 protein represents an emerging biomarker in many solid tumor histologies. Given the various roles it plays in oncogenesis, including but not limited to angiogenesis, epithelial-to-mesenchymal transition, and cell migration, TEM8 has recently served and will continue to serve as the target of novel oncologic therapies. We review herein the role of TEM8 in oncogenesis. We review its normal function, highlight the additional roles it plays in the tumor microenvironment, and synthesize pre-clinical and clinical data currently available. We underline the protein's prognostic and predictive abilities in various solid tumors by (1) highlighting its association with more aggressive disease biology and poor clinical outcomes and (2) assessing its associated clinical trial landscape. Finally, we offer future directions for clinical studies involving TEM8, including incorporating pre-clinical agents into clinical trials and combining previously tested oncologic therapies with currently available treatments, such as immunotherapy.
Assuntos
Neoplasias , Receptores de Superfície Celular , Humanos , Receptores de Superfície Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas dos Microfilamentos , Neoplasias/terapia , Transformação Celular Neoplásica , Carcinogênese , Biologia , Microambiente TumoralRESUMO
Mitochondrial dysfunction in skeletal muscle fibres occurs with both healthy aging and a range of neuromuscular diseases. The impact of mitochondrial dysfunction in skeletal muscle and the way muscle fibres adapt to this dysfunction is important to understand disease mechanisms and to develop therapeutic interventions. Furthermore, interactions between mitochondrial dysfunction and skeletal muscle biology, in mitochondrial myopathy, likely have important implications for normal muscle function and physiology. In this review, we will try to give an overview of what is known to date about these interactions including metabolic remodelling, mitochondrial morphology, mitochondrial turnover, cellular processes and muscle cell structure and function. Each of these topics is at a different stage of understanding, with some being well researched and understood, and others in their infancy. Furthermore, some of what we know comes from disease models. Whilst some findings are confirmed in humans, where this is not yet the case, we must be cautious in interpreting findings in the context of human muscle and disease. Here, our goal is to discuss what is known, highlight what is unknown and give a perspective on the future direction of research in this area.