38 research outputs found
Nucleo-cytoplasmic transport of proteins and RNA in plants
Merkle T. Nucleo-cytoplasmic transport of proteins and RNA in plants. Plant Cell Reports. 2011;30(2):153-176.Transport of macromolecules between the nucleus and the cytoplasm is an essential necessity in eukaryotic cells, since the nuclear envelope separates transcription from translation. In the past few years, an increasing number of components of the plant nuclear transport machinery have been characterised. This progress, although far from being completed, confirmed that the general characteristics of nuclear transport are conserved between plants and other organisms. However, plant-specific components were also identified. Interestingly, several mutants in genes encoding components of the plant nuclear transport machinery were investigated, revealing differential sensitivity of plant-specific pathways to impaired nuclear transport. These findings attracted attention towards plant-specific cargoes that are transported over the nuclear envelope, unravelling connections between nuclear transport and components of signalling and developmental pathways. The current state of research in plants is summarised in comparison to yeast and vertebrate systems, and special emphasis is given to plant nuclear transport mutants
Accommodating Dynamic Oceanographic Processes and Pelagic Biodiversity in Marine Conservation Planning
Pelagic ecosystems support a significant and vital component of the ocean's productivity and biodiversity. They are also heavily exploited and, as a result, are the focus of numerous spatial planning initiatives. Over the past decade, there has been increasing enthusiasm for protected areas as a tool for pelagic conservation, however, few have been implemented. Here we demonstrate an approach to plan protected areas that address the physical and biological dynamics typical of the pelagic realm. Specifically, we provide an example of an approach to planning protected areas that integrates pelagic and benthic conservation in the southern Benguela and Agulhas Bank ecosystems off South Africa. Our aim was to represent species of importance to fisheries and species of conservation concern within protected areas. In addition to representation, we ensured that protected areas were designed to consider pelagic dynamics, characterized from time-series data on key oceanographic processes, together with data on the abundance of small pelagic fishes. We found that, to have the highest likelihood of reaching conservation targets, protected area selection should be based on time-specific data rather than data averaged across time. More generally, we argue that innovative methods are needed to conserve ephemeral and dynamic pelagic biodiversity
Acute physical exercise can influence the accuracy of metacognitive judgments
Acute exercise generally benefits memory but little research has examined how exercise
affects metacognition (knowledge of memory performance). We show that a single bout of
exercise can influence metacognition in paired-associate learning. Participants completed 30-
min of moderate-intensity exercise before or after studying a series of word pairs (cloudivory), and completed cued-recall (cloud-?; Experiments 1 & 2) and recognition memory tests
(cloud-? spoon; ivory; drill; choir; Experiment 2). Participants made judgments of learning
prior to cued-recall tests (JOLs; predicted likelihood of recalling the second word of each pair
when shown the first) and feeling-of-knowing judgments prior to recognition tests (FOK;
predicted likelihood of recognizing the second word from four alternatives). Compared to noexercise control conditions, exercise before encoding enhanced cued-recall in Experiment 1
but not Experiment 2 and did not affect recognition. Exercise after encoding did not influence
memory. In conditions where exercise did not benefit memory, it increased JOLs and FOK
judgments relative to accuracy (Experiments 1 & 2) and impaired the relative accuracy of
JOLs (ability to distinguish remembered from non-remembered items; Experiment 2). Acute
exercise seems to signal likely remembering; this has implications for understanding the
effects of exercise on metacognition, and for incorporating exercise into study routines