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JUMPING GENE FOSSILS. “Evolution often deactivates DNA transposons, leaving them as introns (inactive gene sequences). In vertebrate animal cells, nearly all 100,000+ DNA transposons per genome have genes that encode inactive transposase polypeptides. In humans, all Tc1-like transposons are inactive.” https://en.m.wikipedia.org/wiki/Transposable_element View in LinkedIn

BIRTH AND DEATH. “Beginnings are often difficult to pinpoint, particularly in life cycles, for life is continuous. Life does not tolerate a break (at most a transitory standstill in a stage of quiescence). Life is a continuing process that started some billions of years ago below the level of multicellularity and will end with the death of the last living being. Nevertheless, each individual life that is based on sexual reproduction has two discrete boundaries: fertilization and death.” https://lnkd.in/d6G9geU View in LinkedIn

PROTECTIONS AGAINST TEs. “Because excessive TE activity can damage exons, many organisms have acquired mechanisms to inhibit their activity. Bacteria may undergo high rates of gene deletion as part of a mechanism to remove TEs and viruses from their genomes, while eukaryotic organisms typically use RNA interference to inhibit TE activity. Nevertheless, some TEs generate large families often associated with speciation events.” (TE = transposable elements, jumping genes). https://en.m.wikipedia.org/wiki/Transposable_element View in LinkedIn

SELFISH DNA PARASITES. “While some TEs confer benefits on their hosts, most are regarded as selfish DNA parasites. In this way, they are similar to viruses. Various viruses and TEs also share features in their genome structures and biochemical abilities, leading to speculation that they share a common ancestor.” (TE = transposable elements, jumping genes). https://en.m.wikipedia.org/wiki/Transposable_element View in LinkedIn

TRANSPOSABLE ELEMENTS (TEs) “are found in almost all life forms, and the scientific community is still exploring their evolution and their effect on genome evolution. It is unclear whether TEs originated in the last universal common ancestor, arose independently multiple times, or arose once and then spread to other kingdoms by horizontal gene transfer.” (TE = transposable elements, jumping genes). https://en.m.wikipedia.org/wiki/Transposable_element View in LinkedIn

JUMPING GENES FROM VIRUSES. “Most viruses gave rise to just a few endogenous elements per host genome, but some have spawn massive genomic invasions.” https://www.sciencedirect.com/science/article/pii/S0959437X17301685 View in LinkedIn

DEFINITION. “Transposable elements (TEs) are segments of DNA able to move from one locus to another in a given genome and to replicate themselves in the process.” https://www.sciencedirect.com/science/article/pii/S0959437X17301685 View in LinkedIn

GENE SHUFFLING. “It has long been known that genes change their chromosome locations, and it has been speculated that transposons mobilize large DNA segments because they are often found at the ends of inverted or transposed sequence.” https://lnkd.in/dPjYT-k View in LinkedIn

MOBILE GENES. “A transposable element (TE or transposon) is a DNA sequence that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transposition often results in duplication of the same genetic material. Barbara McClintock's discovery of these jumping genes earned her a Nobel Prize in 1983.” https://en.m.wikipedia.org/wiki/Transposable_element View in LinkedIn

JUMPING GENES AND SPECIATION. “A burst of transposable elements (TEs) is a massive outbreak that may cause radical genomic rebuilding. This phenomenon has been reported in connection with the formation of taxonomic groups and species and has therefore been associated with major evolutionary events in the past.” https://lnkd.in/dtHjQH5 View in LinkedIn