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Plastic microbeads ban enters force in UK View in LinkedIn

SO ENDS this summary of Professor Denis Nobel’s thinking, as outlined in his book Dance to the Tune of Life. The central dogma of molecular biology was formulated by Francis Crick in 1958. Often stated as “DNA makes RNA and RNA makes protein”, in essence it states that once information gets into protein, it cannot get out again, and is unidirectional in flow, and information cannot flow from protein to protein or from protein to nucleic acid. Well, in the sixty years since this proposition, we have learned a lot, and the dogma has been modified. https://lnkd.in/eQDmUtj View in LinkedIn

NORMAL WITH EXCEPTIONS, of course. "Although meiosis is highly conserved in eukaryotes, deviations from the norm are ubiquitous and may provide important insights into its evolution." https://lnkd.in/e2tp_G5 View in LinkedIn

NEO-DARWINISM AND THE SELFISH GENE take a knock with this lecture by Professor Denis Nobel. https://lnkd.in/eUunJpa View in LinkedIn

"A RECURRENT THEME in most meiosis mysteries is the impact of genetic conflicts and selfish genetic elements. As for many genomic features, their impact is probably central, but in many cases, they remain hypothetical and difficult to study directly." https://lnkd.in/e2tp_G5 View in LinkedIn

HOTSPOTS. "The localisation of recombination events differs between species. In many species, recombination occurs in localised regions known as “recombination hotspots” of around 1-2kb in length, although some species (e.g., C. elegans and Drosophila) lack well-defined hotspots." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

SEX DIFFERENCES. "Meiotic drive systems are often entirely distinct between males and females and may be a primary cause of haploid selection." https://lnkd.in/e2tp_G5 View in LinkedIn

ANIMALS VS PLANTS. "Models point to a role of sex differences in selection during the haploid phase. Whilst a viable explanation in plants, there is little empirical support for this in animals, in which meiosis in females is only completed after fertilisation, so there is no true haploid phase, and the small number of expressed genes in sperm." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

UNEQUAL RECOMBINATION. "More intriguing are the quantitative differences between males and females, known as heterochiasmy, which are found in many taxa, but whose mechanistic and evolutionary drivers are not yet fully understood." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

EXTREME CASE. "In many species, cross-over rates and localisation differ between male and female meioses, and can differ in degree and direction even between closely related species. The most extreme case is achiasmy, an absence of recombination in one sex, nearly always the heterogametic sex. This may have evolved either as a side effect of selection to suppress recombination between the sex chromosomes." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn