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Haploview Data Αποθηκεύστε τα αρχεία σε ένα φάκελο με το ονομα "Data" | Full transcriptomics στον ιξό (Viscum album) με 39.000 γονίδια Researchers gain insights into the genome of European mistletoe by Leibniz Universität Hannover Researchers around the world are working on decoding the genomes of plants. Detailed knowledge on biochemical processes in plants can provide important contributions to agriculture, environmental protection and medicine. A team of researchers from Leibniz University Hannover (LUH) has now succeeded in gaining insights into the genome of European mistletoe, Viscum album. Mistletoe is a semi-parasitic evergreen flowering plant that grows on branches of various trees and is characterized by a very special life cycle. Moreover, mistletoe is known for its special secondary compounds, which are used in the treatment of numerous diseases. However, the genome of mistletoe could not be analyzed so far due to its exceptional size. With around 90 billion nucleotides—the basic building blocks of the genome—the mistletoe genome is approximately 30 times larger than the human genome. In order to analyze the mistletoe genome, scientists around Lucie Schröder, Dr. Hans-Peter Braun and Dr. Helge Küster from the Institute of Plant Genetics at LUH used a trick: The genome, which consists of DNA, was not analyzed directly. Instead, transcripts of the genome (RNAs), which code for the mistletoe's proteins, were isolated and transcribed into DNA using enzymes. The resulting shorter DNA molecules could then be subjected to systematic sequence analysis. This way, the researchers were able to determine more than 39,000 mistletoe gene sequences and predict corresponding protein sequences. For the first time, they succeeded in making a systematic inventory of which proteins and thus enzymes occur in mistletoe and which metabolic pathways this plant can perform. Among them are numerous known enzymes that are generally important for life processes in plants, but also special mistletoe proteins, such as viscotoxins and viscolectins, which are considered to possess significant medicinal potential. Furthermore, the researchers were able to demonstrate that the DNA of the protein-coding sections of the mistletoe genome is characterized by a particularly high stability compared to the DNA of other flowering plants. This could contribute to the stress resistance properties of mistletoe. "We can learn a lot from studying parasites and semi-parasites since they do not have to carry out all life processes themselves," explains Dr. Hans-Peter Braun. "If certain structures are missing, it becomes clearer what they are good for and how exactly they function." Mistletoe, for example, has a special respiratory mechanism. Studying this mechanism could also contribute to a better understanding of malfunctions of the respiratory chain in humans and animals during diseases. The results of the research project were recently published in the British scientific journal The Plant Journal. The project can initially be seen as the beginning of a systematic molecular characterisation of mistletoe, since so far only a small part of the DNA sequences determined could be evaluated. In order to encourage further analyses, a public database has been set up in which more than 39,000 gene sequences can be accessed. The researchers anticipate that the use of this database will greatly promote future research activities relating to this extraordinary plant. The database is available at viscumalbum.pflanzenproteomik.de/ https://onlinelibrary.wiley.com/doi/10.1111/tpj.15558 | Γιατί οι βάτραχοι στο Τσερνόμπιλ έγιναν μαύροι; https://theconversation.com/chernobyl... https://en.wikipedia.org/wiki/Effects... https://www.nature.com/articles/s4159... Chernobyl fungus video: https://youtu.be/S-9zFUPTJ0g Synthetic melanin video: https://youtu.be/I50EEKzrOd4 More info about the Iranian city and radiation on Mars: https://www.youtube.com/watch?v=aTBnj... #chernobyl #frogs #melanin | Evolution - What Darwin Never Knew - NOVA Full Documentary HD "What Darwin Never Knew" offers answers to riddles that Darwin couldn't explain. Breakthroughs in a brand-new science—nicknamed "evo devo"—are linking the enigmas of evolution to another of nature's great mysteries, the development of the embryo. NOVA takes viewers on a journey from the Galapagos Islands to the Arctic, and from the explosion of animal forms half a billion years ago to the research labs of today. Scientists are finally beginning to crack nature's biggest secrets at the genetic level. The results are confirming the brilliance of Darwin's insights while revealing clues to life's breathtaking diversity in ways the great naturalist could scarcely have imagined. | Did Humans Almost Go Extinct? 70,000 years ago, the human population hit a major bottleneck, and scientists aren't exactly sure why. | The Journey of Man: A Genetic Odyssey "You and I, in fact everyone allover the world, we're all literally African under the skin; Brothers and sisters separated by a mere 2.000 generations. Oldfashioned concepts of race are not only socially divisive, but scientifically wrong. It's only when we've fully taken this onboard, that we can say with any conviction that the journey our ancestors launched all those years ago, is complete." | Genetic Recombination and Gene Mapping In this video Paul Andersen explains how the frequency of recombination between linked genes can be used to determine the relative location of genes on a chromosome. Thomas Hunt Morgan and Alfred Strutevant used the fruit fly to develop a theory of chromosomal inheritance and discover crossing over. | The evolution of flowering plants. Flowering plants arrived relatively late in geological time, between 290 to 145 million years ago. But once here, they evolved quickly and often displaced many other types of plants. In fact, in terms of species, flowering plants are the dominant plant form on Earth today with more than 300,000 types. Learn how their unique reproductive mechanisms led to this explosion of speciation in such a relatively short time. This free video comes from the course Plant Science: An Introduction to Botany. Watch the rest of the course and start your FREE trial of The Great Courses Plus here: https://www.TheGreatCoursesPlus.com/s... | Principles of Evolution, Ecology and Behavior Σειρά 36 διαλέξεων εξελικτικής οικολογίας από τον καθηγητή SC Stearns στο Yale.
author: Stephen C. Stearns, Department of Ecology and Evolutionary Biology, Yale University
recorded by: Yale University released under terms of: Creative Commons Attribution No Derivatives (CC-BY-ND) This curse presents the principles of evolution, ecology, and behavior for students beginning their study of biology and of the environment. It discusses major ideas and results in a manner accessible to all Yale College undergraduates. Recent advances have energized these fields with results that have implications well beyond their boundaries: ideas, mechanisms, and processes that should form part of the toolkit of all biologists and educated citizens.
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