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FRAGMENT FROM NATURE continues from last weekend on the evo-devo concept. This paper examines the genetic basis for flower morphological adaptive changes. These include genetic redundancy, the fact that morphology genetic drivers are different from metabolic pathway drivers. The multi-level and nuanced capacities of the plant genome are exemplified in how flowers may change shape to adapt to new conditions. View in LinkedIn

VIRAL MACHINERY MIRROR OPPOSITE. "Coevolution between retroviruses and cells resulted in a surprising phenomenon: similarities between viruses and host anti-viral defense machineries. Each component of the virus has an equivalent in the cellular antiviral defense system." https://lnkd.in/eGaw2Kq View in LinkedIn

COMPLEX VIRAL SYMBIOSIS. "The wasps use their onboard viruses, called bracoviruses, to control the development and immunity of the caterpillars they parasitize. The wasps use the viral genes to make virus-like particles containing genes for a toxin, which they insert into their caterpillar prey when they lay their eggs. The infected caterpillar then acts as an incubator for the wasp eggs. Meanwhile, the toxin is made by the caterpillar and poisons its immune system, causes paralysis and stops the caterpillar from pupating." https://lnkd.in/d-szGeg View in LinkedIn

VIRAL DNA IS ACTIVE IN OUR GENOMES. "35-Mio-year-old endogenous HERVs can play a role in gene regulation and cancer formation to this very day. Only about 2% of the human DNA codes for protein products. This is only twice as much as in flies, worms and weeds. However, the genes are about 100-fold larger in humans, allowing complex regulation of gene expression, and with splicing, the number of coding genes is even higher. The human genome contains about 40,000 HERVs today." https://lnkd.in/eGaw2Kq View in LinkedIn

VIRUSES ARE US. "The human genome is full of transposable elements (TEs), endogenous viruses and various retroelements, which correspond to almost 50 % of the human genome. Infection of germline cells led to the accumulation of viral genes during evolution and made the human genome a “graveyard” of retroviral fossils." https://lnkd.in/eGaw2Kq View in LinkedIn

EVOLUTION. "Salvador Luria mused about the viral influence on evolution in 1959. “May we not feel,” he wrote, “that in the virus, in their merging with the cellular genome and reemerging from them, we observe the units and process which, in the course of evolution, have created the successful genetic patterns that underlie all living cells?” http://www.scientificamerican.com/article.cfm?id=are-viruses-alive-2004&page=3 View in LinkedIn

SOME CONSENSUS: "eukaryotic genomes have a chimaeric nature: genes for information storage and processing are archaea-related, and genes for metabolic or ‘operational’ processes are mostly bacterial in nature (but not necessarily derived from the mitochondrial progenitor)." https://lnkd.in/dtPERjK View in LinkedIn

"EXPRESSION can be influenced by changes to variable upstream TF binding regions (cis-regulatory elements), by changes to coding sequences that alter protein–protein interactions essential for transcriptional regulation, by changes in heterochromatin location that silence or unsilence expression, or by changes in copy number that result in additional genes that can be coexpressed or subfunctionalized to effect new expression patterns." (TF = transcription factors). https://lnkd.in/dD4GcAS View in LinkedIn

"VIRAL PARTICLES are much more abundant than cells and viral genes outnumber cellular ones in the biosphere. Cellular genomes also harbour many integrated viruses whereas cellular genes are rare in viral genomes. The gene flux from virus to cell is thus overwhelming if compared with the opposite event. Cells are giant pickpockets of viral genes and can mimic viral biology." http://www.sciencedirect.com/science/article/pii/S1879625713001077 View in LinkedIn

LARGE IMPACT OF CODING CHANGES. "Across the diversity of life there is, by and large, considerable conservation of protein coding sequences; still, the number of coding changes that have the capacity to impact gene regulation, protein interactions and DNA-binding properties can be significant." https://lnkd.in/dD4GcAS View in LinkedIn