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Muscle fiber-type specific expression of UCP3-protein is reported here for the firts time, using immunofluorescence microscopy
Meer bewegen vraagt meer energie. Het lijkt daarom logisch te veronderstellen dat wie beweegt daardoor ook meer gaat eten. Heeft het dan wel zin om meer te gaan bewegen om af te vallen. In dit artikel wordt een wiskundig model opgesteld. De "energiebalans" kan worden beschreven met een eerste orde lineaire differentiaalvergelijking. Oplossing van deze vergelijking laat zien dat het inderdaad zin heeft om meer te bewegen.
The Amsterdam University of Applied Sciences started a research and education group on Applied Quantum Computing at September 1st 2020. This group has a focus on Quantum Computing and Quantum Sensing. Quantum Computing is done together with the Computer Science program and Quantum Sensing with the new Technical Physics program which will start September 1st 2021. The group is involved in educational efforts to create a general awareness of Quantum Computing under the umbrella of the innovation hub Quantum.Amsterdam. In February 2021 the group starts a minor Applied Quantum Computing. Students learn how to program quantum algorithms and together with companies such as Capgemini, Qu & Co and SURFsara engage in projects solving real problems.
Carnitine/choline acyltransferases play diverse roles in energy metabolism and neuronal signalling. Our knowledge of their evolutionary relationships, important for functional understanding, is incomplete. Therefore, we aimed to determine the evolutionary relationships of these eukaryotic transferases. We performed extensivephylogenetic and intron position analyses. We found that mammalian intramitochondrial CPT2 is most closely related to cytosolic yeast carnitine transferases (Sc-YAT1 and 2), whereas the other members of the family are related to intraorganellar yeast Sc-CAT2. Therefore, the cytosolically active CPT1 more closely resembles intramitochondrial ancestors than CPT2. The choline acetyltransferase is closely related to carnitine acetyltransferase and shows lower evolutionary rates than long chain acyltransferases. In the CPT1 family several duplications occurred during animal radiation, leading to the isoforms CPT1A, CPT1B and CPT1C. In addition, we found five CPT1-like genes in Caenorhabditis elegans that strongly group to the CPT1 family. The long branch leading to mammalian brain isoform CPT1C suggests that either strong positive or relaxed evolution has taken place on this node. The presented evolutionary delineation of carnitine/choline acyltransferases adds to current knowledge on their functions and provides tangible leads for further experimental research.
MULTIFILE
Control of plant growth is an important aspect of crop productivity and yield in agriculture. Overexpression of the At CHR12/ 23 genes in Arabidopsis thaliana reduced growth habit without other morphological changes. These two genes encode Snf2 chromatin remodelling ATPases. Here, we translate this approach to the horticultural crop tomato ( Solanum lycopersicum). We identified and cloned the single tomato ortholog of the two Arabidopsis Snf2 genes, designated Sl CHR1. Transgenic tomato plants (cv. Micro-Tom) that constitutively overexpress the coding sequence of Sl CHR1 show reduced growth in all developmental stages of tomato. This confirms that Sl CHR1 combines the functions of both Arabidopsis genes in tomato. Compared to the wild type, the transgenic seedlings of tomato have significantly shorter roots, hypocotyls and reduced cotyledon size. Transgenic plants have a much more compact growth habit with markedly reduced plant height, severely compacted reproductive structures with smaller flowers and smaller fruits. The results indicate that either GMO-based or non- GMO-based approaches to modulate the expression of chromatin remodelling ATPase genes could develop into methods to control plant growth, for example to replace the use of chemical growth retardants. This approach is likely to be applicable and attractive for any crop for which growth habit reduction has added value.
Common cloning is often associated with instability of certain classes of DNA. Here we report on IS1 transposition as possible source of such instability. During the cloning of Arabidopsis thaliana gene into commercially available vector maintained in widely used Escherichia coli host the insertion of complete IS1 element into the intron of cloned gene was found. The transposition of the IS1 element was remarkably rapid and is likely to be sequence-specific. The use of E. coli strains that lower the copy number of vector or avoiding the presence of the problematic sequence is a solution to the inadvertent transposition of IS1. The transposition of IS1 is rare but it can occur and might confound functional studies of a plant gene.
The exploitation of the metagenome for novel biocatalysts by functional screening is determined by the ability to express the respective genes in a surrogate host. The probability of recovering a certain gene thereby depends on its abundance in the environmental DNA used for library construction, the chosen insert size, the length of the target gene, and the presence of expression signals that are functional in the host organism. In this paper, we present a set of formulas that describe the chance of isolating a gene by random expression cloning, taking into account the three different modes of heterologous gene expression: independent expression, expression as a transcriptional fusion and expression as a translational fusion. Genes of the last category are shown to be virtually inaccessible by shotgun cloning because of the low frequency of functional constructs. To evaluate which part of the metagenome might in this way evade exploitation, 32 complete genome sequences of prokaryotic organisms were analysed for the presence of expression signals functional in E. coli hosts, using bioinformatics tools. Our study reveals significant differences in the predicted expression modes between distinct taxonomic groups of organisms and suggests that about 40% of the enzymatic activities may be readily recovered by random cloning in E. coli.
