Category: Uncategorized

OBSCURE RNA VIRUSES. "Most of these analyses have focused on viruses with genomes that are made of DNA or positive-sense RNA, and there have been fewer studies of viruses with genomes made of negative-sense RNA. Therefore, the evolutionary history of negative-sense RNA viruses, which are responsible for influenza, measles, Ebola and many other diseases in animals and plants, remains obscure." https://lnkd.in/dYBnxsT View in LinkedIn

OVER 100 NEW VIRUSES FOUND. "Zhang and co-workers found that the 112 new viruses were spread across the major lineages of the negative-sense RNA viruses. These discoveries fill some major gaps in our knowledge, and allow the tree of viral relationships to be updated. For example, this latest work confirms that the viruses of the Arenaviridae genus—which generally infect rodents—belong to the Bunyaviridae family along with two previously unclassified genera of viruses that infect plants." A drop in the bucket. https://lnkd.in/dYBnxsT View in LinkedIn

MODULAR VIRAL DIVERSITY. "When considering viral diversity at the genus level, the network displays a modular topology. These results confirmed the prediction that ‘at macroevolutionary scales, host–phage interaction matrices should be typified by a modular structure’, as also had been observed across 215 phage types against 286 host types of unknown diversity." https://elifesciences.org/content/4/e08490 View in LinkedIn

BLACK HOLE. "While recent advances in high-throughput sequencing and viral metagenomics continue to expand the bounds of viral sequence space, such viruses are typically unlinked to cognate hosts, severely limiting ecological and evolutionary inferences." https://lnkd.in/dYBnxsT View in LinkedIn

CHALLENGES. "Studying the genetics of the viruses in these communities is challenging. There is no single ‘marker’ gene that can be used to identify all viruses in environmental samples. Also, many of the fragments of viral genomes that have been identified have not yet been linked to their host microbes. Many viruses integrate their genome into the DNA of their host cell, and there are computational tools available that exploit this ability to identify viruses and link them to their host. However, other viruses can live and multiply inside cells without integrating their genome into the host's DNA." https://elifesciences.org/content/4/e08490 View in LinkedIn

HEART OF EVOLUTION. “Even though chromosomal rearrangements have been associated with diseases and reduced fitness, they are also major drivers of evolution. They contribute to adaptation to novel or changing environments and even to speciation by reproductive isolation.” https://lnkd.in/eC8eb-V View in LinkedIn

STACKED DECK. “Outcrossing mutations would have to overcome both the transmission advantage of selfing and the greater seed production of plants capable of self-fertilization. These are potentially large disadvantages at the gene and individual levels.” http://onlinelibrary.wiley.com/doi/10.1111/nph.12182/full View in LinkedIn

GENOMIC VARIATION. “Variations are caused by a multitude of mechanisms and range from single nucleotide polymorphisms to large-scale genomic rearrangements. The latter may result in translocation, duplication, and deletion of genetic material, thereby affecting chromosomal size and gene content.” https://lnkd.in/eC8eb-V View in LinkedIn

MORE RESTRICTIVE. “If selfing evolves because of reproductive assurance, the conditions for a reversal are even more restrictive than if selfing evolves principally because of its transmission advantage, assuming that all else is equal.” https://lnkd.in/dj9hK7n View in LinkedIn

DYNAMIC GENOMES. “Genomes are highly dynamic and vary considerably between, and often even within, species with respect to structure and content. This dynamics is caused by mutations that are either neutral, and may thus be transient, or mediate increased fitness and became fixed in the population by natural (Darwinian) selection.” https://lnkd.in/eC8eb-V View in LinkedIn