Search

RNA 5′ cap structures comprising the metabolic effector nicotinamide adenine dinucleotide (NAD) have been identified in diverse organisms. Here we report a simple, two-step procedure to detect and quantitate NAD-capped RNA, termed “NAD-capQ.” By use of NAD-capQ we quantitate NAD-capped RNA levels in Escherichia coli, Saccharomyces cerevisiae, and human cells, and we measure increases in NAD-capped RNA levels in cells from all three organisms harboring disruptions in their respective “deNADding” enzymes. We further show that NAD-capped RNA levels in human cells respond to changes in cellular NAD concentrations, indicating that NAD capping provides a mechanism for human cells to directly sense and respond to alterations in NAD metabolism. Our findings establish NAD-capQ as a versatile, rapid, and accessible methodology to detect and quantitate 5′-NAD caps on endogenous RNA in any organism.

The chemical nature of the 5′ end of RNA is a key determinant of RNA stability, processing, localization and translation efficiency, and has been proposed to provide a layer of ‘epitranscriptomic’ gene regulation. Recently it has been shown that some bacterial RNA species carry a 5′-end structure reminiscent of the 5′ 7-methylguanylate ‘cap’ in eukaryotic RNA. In particular, RNA species containing a 5′-end nicotinamide adenine dinucleotide (NAD+) or 3′-desphospho-coenzyme A (dpCoA) have been identified in both Gram-negative and Gram-positive bacteria. It has been proposed that NAD+, reduced NAD+(NADH) and dpCoA caps are added to RNA after transcription initiation, in a manner analogous to the addition of 7-methylguanylate caps. Here we show instead that NAD+, NADH and dpCoA are incorporated into RNA during transcription initiation, by serving as non-canonical initiating nucleotides (NCINs) for de novo transcription initiation by cellular RNA polymerase (RNAP). We further show that both bacterial RNAP and eukaryotic RNAP II incorporate NCIN caps, that promoter DNA sequences at and upstream of the transcription start site determine the efficiency of NCIN capping, that NCIN capping occurs in vivo, and that NCIN capping has functional consequences. We report crystal structures of transcription initiation complexes containing NCIN-capped RNA products. Our results define the mechanism and structural basis of NCIN capping, and suggest that NCIN-mediated ‘ab initio capping’ may occur in all organisms.

A brief visit to Monuriki, an island in Fiji’s Mamanuca group was completed in March-April 2011 to gather baseline data on the island’s population of Wedge-tailed Shearwaters Puffinus pacificusprior to the eradication of alien invasive Polynesian Rat Rattus exulansand feral goats Capra hircusfrom the island in December 2011. We estimated an island-wide population of 2,000-5,500 pairs of Wedge-tailed Shearwaters, the largest population recorded in Fiji. Productivity was estimated to be 40%. It is anticipated these baseline figures will be used to assess the impacts that the removal of invasive mammals has on the population.

The article presents research which examined the habitat associations of Manchurian Reed Warbler Acrocephalus tangorum at significant wintering sites in Cambodia. Researchers conducted fieldwork in March 2006 to examine their habitat associations during the dry and wet seasons. They found that the species has apparent bias towards grass habitats.

The article discusses the results of a survey to determine the population size and distribution of the critically endangered Spoon-billed Sandpiper (SBS) in Bangladesh. The study examined the importance of Bangladesh as a wintering spot for the birds, the birds' foraging ecology and habitat preference, and potential threats. 49 SBS were recorded at three locations and showed a preference for firm sandy intertidal mudflats. Threats to the birds and conservation recommendations are noted.

The World Commission on Dams was initiated as a new form of global policy making to find a way beyond the intensifying conflicts over dam projects. It was established by diverse groups to conduct an independent global review of the performance and impacts of large dams and develop internationally acceptable criteria and guidelines for the future. The Commission's Report, Dams and Development: a New Framework for Decision Making, presents an integrated assessment of how large dams have performed against their development targets and what the costs and impacts have been. Performance was highly variable, with a considerable portion of those studied falling short of physical targets, while many continue to generate benefits beyond their projected economic life. Many were less profitable in economic terms than expected, indicating that there is considerable scope for improving performance of existing projects. The Commission considered the adverse impacts on ecosystems and people's livelihoods to be unacceptable and unnecessary. To move forward beyond conflict, the Commission presents a new framework for decision-making. It rejects the notion of trading one person's gain against another's loss and proposes an approach based on recognising rights and assessing risks for identifying legitimate stakeholders and negotiating development outcomes. Seven strategic priorities and corresponding policy principles for water and energy resources development were derived from this approach and a series of practical criteria and guidelines are presented. The Commission's recommendations require more attention to be paid to the preliminary stages of planning. This has time and cost implications, but in the long run, the Commission's Report offers the opportunity to reduce conflict, reduce delays and lower overall costs to the operator, the government and to society in general. Copyright © 2001 John Wiley & Sons Ltd.

The World Commission on Dams was initiated as a new form of global policy making to find a way beyond the intensifying conflicts over dam projects. It was established by diverse groups to conduct an independent global review of the performance and impacts of large dams and develop internationally acceptable criteria and guidelines for the future.

The distributions of host-specific herbivorous insects along latitudinal and altitudinal gradients, particularly within arctic and alpine environments, provide useful analogs for predicted future changes that are likely to occur over time at any one location, given a gradually changing thermal environment. It is suggested that selected examples of these insect/plant systems can serve as highly responsive sensors of changing climatic temperatures. Distributions of insects that show a restricted occurrence withinthe overall range of their host plant are predicted to respond more rapidly than the distribution of the host plants themselves. Examples are given to show how these insect-plant systems might be used to monitor long-term temperature change. These examples, drawn from both our published and unpublished work on Homoptera (Insecta), include the following common and widely distributed host plant species within the Northern Hemisphere: Dryas octopetala, Chamerion angustifolium, dwarf Salixspecies including S. lapponum, and Calluna vulgaris/Erica cinerea.

The article focuses on a study on the status of Red-throated pipit Anthus cervinus in Bangladesh. It cites the increasing band of experienced local ornithologists under the auspices of the Bangladesh Bird Club and other organisations. It provides a comparison between the summer-plumaged birds and summer-plumaged Rosy Pipits. Red-throated Pipits typically foraged singly, presumably to avoid competition with both conspecifics and allospecifics.