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1.
Many crops in developing countries suffer devastating attacks from insect pests. Expression of insecticidal proteins in genetically engineered (GE) crops is a potentially powerful means of controlling such pests. Potentially harmful effects of these crops on non‐target organisms (NTOs) is of major concern as many of those provide important ecological functions such as pest regulation. Consequently, the likelihood of adverse effects of insect‐resistant GE crops on NTOs is assessed case‐by‐case as part of environmental risk assessments that inform regulatory decision‐making. While risk assessments should be rigorous, it is vital that regulatory barriers do not unnecessarily restrict or prevent the application of genetic engineering to important crops in those countries. Efficient regulatory decision‐making should make effective use of published information on the biology and ecology of the crop in the country where approval is sought, along with regulatory data produced for GE insect‐resistant crops that have received regulatory approvals elsewhere. Just as the risks are assessed for each GE crop individually, the amount of new regulatory data required for a GE crop should vary between crops depending on the amount of existing data and the severity of the perceived risks: new data should be collected only if existing data do not corroborate identified risk hypotheses with sufficient certainty. In this paper, we illustrate how such an approach could work using risks to NTOs from insect‐resistant GE pigeonpea in India as an example.  相似文献   

2.
The novelty of synthetic biology lies in the use of synthesized parts that can be arranged to make useful products. Such advanced, high-throughput genetic engineering projects redesign and fabricate existing biological systems as well as new biological parts, devices and systems that do not occur in nature. This Opinion discusses challenges raised by synthetic biology for public acceptance, regulation, commercialization and the emerging global issue of access to genetic resources and information. As with all new fields of research, maintaining the trust of the public and policy regulators is paramount. Hype and exaggerated claims are counterproductive to developing adaptive and ethically sound regulatory models responsive to stakeholder concerns.  相似文献   

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4.
What regulatory requirements must be met before a new medical device can be marketed in the USA? In this article, David Thomas reviews the regulations, examines the impact of recent legislation and looks at the emerging trend towards international harmonization of the regulation of health care products.  相似文献   

5.
With the emergence of CRISPR technology, targeted editing of a wide variety of genomes is no longer an abstract hypothetical, but occurs regularly. As application areas of CRISPR are exceeding beyond research and biomedical therapies, new and existing ethical concerns abound throughout the global community about the appropriate scope of the systems' use. Here we review fundamental ethical issues including the following: 1) the extent to which CRISPR use should be permitted; 2) access to CRISPR applications; 3) whether a regulatory framework(s) for clinical research involving human subjects might accommodate all types of human genome editing, including editing of the germline; and 4) whether international regulations governing inappropriate CRISPR utilization should be crafted and publicized. We conclude that moral decision making should evolve as the science of genomic engineering advances and hold that it would be reasonable for national and supranational legislatures to consider evidence-based regulation of certain CRISPR applications for the betterment of human health and progress.  相似文献   

6.
Significant advances over the last few years have seen plant-made pharmaceuticals (PMPs) move from the exploratory research phase towards clinical trials, with the first commercial products for human use expected to reach the market by 2009. Europe has yet to witness the commercial application of PMP technology, although at least one product has begun phase II clinical trials with others following close behind. These emerging products are set to challenge the complex and overlapping regulations that currently govern GM plants and ‘conventional’ pharmaceutical production. The areas of responsibility are being mapped out between the different EU regulatory agencies, with specific guidelines currently being drawn up for the regulation of PMPs. This article discusses issues surrounding the development of robust risk-assessment and risk-management practices based on health and environmental impact, while working with EU regulatory authorities to ensure appropriate regulatory oversight.  相似文献   

7.
This paper explores the syncretic accommodations made by North Mekeo (PNG) villagers arising from recent historical encounters with Catholic (Sacred Heart) missionaries over issues of ritual authenticity and effectiveness, personhood, and agency in a wider field of Christian evangelism and globalisation. Through a careful examination and comparison of pre‐existing ritual notions and practices (e.g., sorcery techniques, mortuary ritual performance, gender rituals) and the recent trends of commodification and enthusiastic Catholic charismatic performance, what might appear to be incongruous religious beliefs and practices are shown to possess numerous remarkably compatible similarities at the level of explicit cultural categorisation and ritual enactment. In accord with long‐standing anthropological arguments, recent North Mekeo syncretism thus consists of an integrated, albeit transformed rather than ‘confused’, mixing of indigenous and exogenous religious elements. Further, in this analysis of recent Melanesian religious change syncretism implies a novel conceptual convergence between syncretic processes and the dynamics of personhood, sociality and agency as construed in the framework of the ‘new Melanesian ethnography’.  相似文献   

8.
细菌对胁迫应答因子RpoS的调控   总被引:1,自引:0,他引:1  
RpoS是细菌一般胁迫反应的主要调控因子,可以诱导RpoS表达的胁迫条件包括碳源和氮源饥饿、渗透压升高、低pH、温度升高等。在细菌体内,大量环境和细胞内信号参与RpoS的调控。这些调控可以发生在转录和翻译水平、降解过程以及活性调节等方面,形成一个复杂的调控网络。RpoS调控机制的阐明对于了解胁迫条件下细菌响应机制具有重要意义。  相似文献   

9.
The regulatory role of histone modifications with respect to the structure and function of chromatin is well known. Proteins and protein complexes establishing, erasing and binding these marks have been extensively studied. RNAs have only recently entered the picture of epigenetic regulation with the discovery of a vast number of long non-coding RNAs. Fast growing evidence suggests that such RNAs influence all aspects of histone modification biology. Here, we focus exclusively on the emerging functional interplay between RNAs and proteins that bind histone modifications. We discuss recent findings of reciprocally positive and negative regulations as well as summarize the current insights into the molecular mechanism directing these interactions. This article is part of a Special Issue entitled: Molecular mechanisms of histone modification function.  相似文献   

10.
11.
Historically, the ribosome has been viewed as a complex ribozyme with constitutive rather than intrinsic regulatory capacity in mRNA translation. However, emerging studies reveal that ribosome activity may be highly regulated. Heterogeneity in ribosome composition resulting from differential expression and post-translational modifications of ribosomal proteins, ribosomal RNA (rRNA) diversity and the activity of ribosome-associated factors may generate 'specialized ribosomes' that have a substantial impact on how the genomic template is translated into functional proteins. Moreover, constitutive components of the ribosome may also exert more specialized activities by virtue of their interactions with specific mRNA regulatory elements such as internal ribosome entry sites (IRESs) or upstream open reading frames (uORFs). Here we discuss the hypothesis that intrinsic regulation by the ribosome acts to selectively translate subsets of mRNAs harbouring unique cis-regulatory elements, thereby introducing an additional level of regulation in gene expression and the life of an organism.  相似文献   

12.
Appropriate regulation of stem cell-based products is essential to ensure public safety and trust while minimising unnecessary barriers to product development, but presents numerous challenges. Weaknesses of existing legal frameworks include variation between jurisdictions and poor fit between product categories and new technologies. The new European Regulation on advanced therapy medicinal products is an important attempt to provide a consolidated regulatory framework for novel products. Others can learn from issues encountered in its development, including definition of product categories, ethical concerns, and the application of regulations to small-scale production. Several aspects of the Regulation will be useful models, but some larger questions remain unresolved. As reform efforts move forward, harmonisation and sharing of expertise will be vital to effective regulation.  相似文献   

13.
A major goal of biological research is to provide a mechanistic understanding of diverse biological processes. To this end, synthetic biology offers a powerful approach, whereby biological questions can be addressed in a well-defined framework. By constructing simple gene circuits, such studies have generated new insights into the design principles of gene regulatory networks. Recently, this strategy has been applied to analyze ecological and evolutionary questions, where population-level interactions are critical. Here, we highlight recent development of such systems and discuss how they were used to address problems in ecology and evolutionary biology. As illustrated by these examples, synthetic ecosystems provide a unique platform to study ecological and evolutionary phenomena that are challenging to study in their natural contexts.  相似文献   

14.
Higher-order chromosome organization is emerging as a major determinant of gene regulation. Although the structure of chromatin at the level of individual nucleosomes has been studied in considerable detail, less is known about higher levels of organization. Two new methods have been developed that can be used to obtain detailed information about the higher-order folding of chromatin. Using these methods, long-range looping interactions have been shown to occur upon activation of the murine beta-globin locus, explaining the long-standing question of how gene regulatory elements can act at large genomic distances from their target genes.  相似文献   

15.
This article evaluates New Zealand’s Medicines Amendment Bill 2011. This Bill is currently before Parliament and will amend the Medicines Act 1981. On June 20, 2011, the Australian and New Zealand governments announced their decision to proceed with a joint scheme for the regulation of therapeutic products such as medicines, medical devices, and new medical interventions. Eventually, the joint arrangements will be administered by a single regulatory agency: the Australia New Zealand Therapeutic Products Agency. The medicines regulations in Australia and New Zealand will be updated as part of this process. The Medicines Amendment Bill addresses some of the well-recognised deficiencies in the Medicines Act 1981. However, a comprehensive overhaul of the Act is not being undertaken. I argue that repealing and replacing the Medicines Act 1981 would be preferable and advisable, given the number of legal difficulties with the Act and, in particular, where it does not align with equivalent current international law.  相似文献   

16.
Domestic laws, their implementing regulations and policies, and government and private-party governance programs are now being carefully reviewed and revised to enhance their utility to manage the potential risks posed by nanoscale materials. Whether existing laws and their implementing programs are adequate to address such risks will continue to inspire debate and legislative and regulatory initiatives for years to come. This article reviews existing legal and governance oversight systems and analyzes their strengths and deficiencies in addressing the potential risks posed by nanoscale materials and in fostering nanotechnology's promise. Particular attention is devoted to emerging regulatory approaches the US Environmental Protection Agency is taking under the Toxic Substances Control Act and the Federal Insecticide, Fungicide, and Rodenticide Act, the two domestic chemical product laws primarily responsible for ensuring the safety of chemical substances and mixtures.  相似文献   

17.
Horizontal DNA transfer plays a major role in the evolution of bacteria. It allows them to acquire new traits rapidly and these may confer fitness advantages as the bacteria compete with others in the environment. Historically, the mechanisms of horizontal DNA transfer, chiefly conjugation, transformation and transduction, have received a great deal of attention. Less attention has been focused on the regulatory problems that may accompany the acquisition of new genes by lateral routes. How are these genes integrated into the existing regulatory circuits of the cell? Does a process of 'plug-and-play' operate, or are the new genes silenced pending the evolution of regulatory mechanisms that make their expression not only safe but also beneficial to both the gene and its new host? Recent research shows that bacterial nucleoid-associated proteins such as H-NS, HU and Fis are important contributors to the processes of regulatory integration that accompany horizontal gene transfer. A key emerging theme is the antagonism that exists between the DNA–protein–DNA bridging activity of the H-NS repressor and the DNA-bending and DNA-wrapping activities of regulatory proteins that oppose H-NS.  相似文献   

18.
Spontaneous sharp bending of double-stranded DNA   总被引:13,自引:0,他引:13  
Sharply bent DNA is essential for gene regulation in prokaryotes and is a major feature of eukaryotic nucleosomes and viruses. The explanation normally given for these phenomena is that specific proteins sharply bend DNA by application of large forces, while the DNA follows despite its intrinsic inflexibility. Here we show that DNAs that are 94 bp in length-comparable to sharply looped DNAs in vivo-spontaneously bend into circles. Proteins can enhance the stability of such loops, but the loops occur spontaneously even in naked DNA. Random DNA sequences cyclize 10(2)-10(4) times more easily than predicted from current theories of DNA bending, while DNA sequences that position nucleosomes cyclize up to 10(5) times more easily. These unexpected results establish DNA as an active participant in the formation of looped regulatory complexes in vivo, and they point to a need for new theories of DNA bending.  相似文献   

19.
Transgenic plants that are being developed for commercial cultivation must be tested under field conditions to monitor their effects on surrounding wildlife and conventional crops. Developers also use this opportunity to evaluate the performance of transgenic crops in a typical environment, although this is a matter of commercial necessity rather than regulatory compliance. Most countries have adapted existing regulations or developed new ones to deal specifically with transgenic crops and their commodities. The European Union (EU) is renowned, or perhaps notorious, for having the broadest and most stringent regulations governing such field trials in the world. This reflects its nominal adherence to the precautionary approach, which assumes all transgenic crops carry an inherent risk. Therefore, field trials in the EU need to demonstrate that the risk associated with deploying a transgenic crop has been reduced to the level where it is regarded as acceptable within the narrowly defined limits of the regulations developed and enforced (albeit inconsistently) by national and regional governments, that is, that there is no greater risk than growing an equivalent conventional crop. The involvement of national and regional competent authorities in the decision-making process can add multiple layers of bureaucracy to an already-intricate process. In this review, we use country-based case studies to show how the EU, national and regional regulations are implemented, and we propose strategies that could increase the efficiency of regulation without burdening developers with further unnecessary bureaucracy.  相似文献   

20.
Among the structural phospholipids that form the bulk of eukaryotic cell membranes, phosphatidylinositol (PtdIns) is unique in that it also serves as the common precursor for low‐abundance regulatory lipids, collectively referred to as polyphosphoinositides (PPIn). The metabolic turnover of PPIn species has received immense attention because of the essential functions of these lipids as universal regulators of membrane biology and their dysregulation in numerous human pathologies. The diverse functions of PPIn lipids occur, in part, by orchestrating the spatial organization and conformational dynamics of peripheral or integral membrane proteins within defined subcellular compartments. The emerging role of stable contact sites between adjacent membranes as specialized platforms for the coordinate control of ion exchange, cytoskeletal dynamics, and lipid transport has also revealed important new roles for PPIn species. In this review, we highlight the importance of membrane contact sites formed between the endoplasmic reticulum (ER) and plasma membrane (PM) for the integrated regulation of PPIn metabolism within the PM. Special emphasis will be placed on non‐vesicular lipid transport during control of the PtdIns biosynthetic cycle as well as toward balancing the turnover of the signaling PPIn species that define PM identity.  相似文献   

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