Month: September 2022

SO ENDS the first weekend on evo-devo as an idea. The evolution and development of symmetry in the snapdragon is a topic that has engaged some of our brightest minds. Such focus and attention to the smallest details of a fragment of nature is not only a marvelous luxury but also permits a portal into the greater inner workings of life on planet earth. We are enriched by such scholarship. View in LinkedIn

WHY DNA? "A major question is why was DNA selected to replace RNA? The traditional explanation is that DNA replaced RNA as genetic material because it is more stable and can be repaired more faithfully." https://lnkd.in/dNTbYMw View in LinkedIn

BORROWED MACHINERY. "Most DNA viruses are entirely dependent on the host DNA and RNA synthesizing machinery, and RNA processing machinery, while larger genome viruses encode this machinery themselves. All RNA viruses use their own RNA replicase enzymes to replicate their genomes." https://lnkd.in/dNTbYMw View in LinkedIn

LARGER GENOMES. "Replacement of RNA by DNA as genetic material has thus opened the way to the formation of large genomes, a prerequisite for the evolution of modern cells. The above scenario nicely explains why, through Darwinian competition, cell populations with DNA genomes finally eliminated cells with RNA genomes." https://lnkd.in/dNTbYMw View in LinkedIn

CRITICAL ROLE. "The idea that viruses have played a critical role in the origin of DNA is in line with previous conception that retroviruses were relics of the RNA/DNA world transition." https://lnkd.in/dNTbYMw View in LinkedIn

ANCIENT PLAYERS. "These speculations on the origin of DNA fit well with hypotheses on viral origin that consider no longer viruses as fragments of genetic materials recently escaped from their hosts, but as ancient players in life evolution, possibly predating the divergence between the three domains of life." https://lnkd.in/dNTbYMw View in LinkedIn

MORE FLEXIBLE. "In contrast to cellular genomes, which are all made of double-stranded DNA, viral DNA genomes are very diverse." https://lnkd.in/dNTbYMw View in LinkedIn

RANGE OF SOPHISTICATION. "Some DNA viruses replicate their genome using only replication proteins encoded by their host (with the exception of initiator proteins). However, many large DNA viruses encode also several proteins involved in the elongation step of DNA replication." https://lnkd.in/dNTbYMw View in LinkedIn

VIRAL UPPER RANGE. "Some of them (e.g., T4-phages) have reached a high level of complexity in their DNA replication machinery, and consequently encode functional analogs for all proteins involved in cellular DNA replication." https://lnkd.in/dNTbYMw View in LinkedIn

VIRUS TO EUKARYOTIC CELLS. "If DNA and DNA replication proteins originated in viruses, one can imagine that DNA replication mechanisms have been transferred from viruses to cells. Many protein phylogenies support the idea of ancient transfers of replicative proteins between cells and viruses." https://lnkd.in/dNTbYMw View in LinkedIn