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ORIGIN OF PLOIDY. "Polyploids are known to originate within individuals, or following hybridization between closely related populations (auto-polyploidy), or from interspecific hybridization events (allopolyploidy)." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

BREATHTAKING INSIGHTS. "Nowhere is the pace of progress more apparent than in plant evolutionary genomics, where the application of massively parallel sequencing approaches and advances in computational and bioinformatic capabilities have led to breathtaking insights about the structure, evolution, and function of plant genomes and their various genomic residents." https://lnkd.in/eiPytFX View in LinkedIn

"A GENE'S LINEAGE might have begun by being on a recessive subgenome but subsequently accumulates mutations that lower expression further (e.g., various enhancer deletions, less efficient splice joints, point mutations in the core promoter), including continued accumulation of TE insertions and the mutations caused upon TE excisions. It seems fortunate that we could even measure genome dominance as separate from gene expression." (TE = transposable element). https://lnkd.in/bCmw3Fr View in LinkedIn

SELECTIVE PROCESS. "One intriguing and only partially understood dimension of the genomic diploidization process is that it may be nonrandom with respect to the types of genes retained in duplicate and those returned to single-copy status by mutation." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

SUBGENOME INEQUALITY. "Once genome dominance is established during the initial inbreeding generations following the polyploidy event itself, genes on one subgenome tend to express less than genes on the other. We predict that this essential inequality begins a cascade of mutational differences based on nothing more profound than “a less expressed gene is easier to mutate” or alter by recombination." https://lnkd.in/bCmw3Fr View in LinkedIn

ANCESTRAL FOOTPRINTS. "This diploidization phenomenon reflects mechanistically diverse processes, operating collectively and over the long haul, ultimately leading to contemporary descendants that behave cytogenetically as normal diploids while harboring in their genomes the vestigial evidence of past polyploidy events." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

BLOOM AND PURGE. "We hypothesize that when two genomes come together in an allotetraploid, one genome has invariably made compromises to a different level than the other based on differences in transposon bloom-and-purge history and the degree of selection against TE amplification." (TE = transposable element). https://lnkd.in/bCmw3Fr View in LinkedIn

REVERSIBLE POLYPLOIDY. "Thus, it is immediately apparent that polyploidy is, at least in part, reversible, and that over time it is followed by massive chromosomal rearrangements, reductions in chromosome number, and the large-scale loss of both repetitive sequences and duplicated genes all leading to genome downsizing." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

POSITION EFFECT. "Hollister et al., provided strong evidence that TE silencing represents a tradeoff between the primary selection to reduce transposon expression and the consequent reduction in levels of gene expression for genes near transposons via a position effect whereby the silencing of the transposon spreads to an adjacent gene’s promoter." (TE = transposable element). https://lnkd.in/bCmw3Fr View in LinkedIn

THEORY VS PRACTICE 2. "Similarly, and notwithstanding the uncertainty regarding actual ancestral angiosperm genome sizes, if one postulates a small ancestral genome size of, say, 300 megabases, in the absence of countervailing forces the modern G. hirsutum genome should be enormous, 43.2 gigabases (Gb), instead of the 2.4 Gb that it actually contains." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn