Category: Uncategorized

EARLY DEARTH. “A decade ago, evolutionary biologists were hesitant to invoke horizontal gene transfer as an explanation for these discrepancies. Then a few cases in which a simple bifurcating tree was clearly an insufficient evolutionary metaphor were recognized.” https://lnkd.in/djKBnru View in LinkedIn

PARTIALLY CONGRUENT. “The impact of such horizontal transfer is that molecular phylogenies calculated for different molecules from the same set of species, while often agreeing in broad outline, are only rarely completely congruent.” https://lnkd.in/djKBnru View in LinkedIn

“HORIZONTAL GENE TRANSFER can occur between even very distantly related organisms, e.g., between bacteria and plants or fungi.” https://lnkd.in/djKBnru View in LinkedIn

PROMISCUOUS AND RULE-BREAKING. “Horizontal, or lateral, gene transfer (HGT) is different, both in mechanism and in impact. Barriers to homologous (legitimate) recombination do not preclude its occurrence—even between very distantly related organisms—because numerous illegitimate means are available for integrating foreign DNA into the genome.” This is the real magic of horizontal gene transfer. https://lnkd.in/djKBnru View in LinkedIn

BACTERIA CASE STUDY. “Similarly, estimates of horizontal gene transfer based on atypical gene content imply that a minority (albeit a significant minority) of genes arrived into these genomes recently by horizontal gene transfer.” https://lnkd.in/djKBnru View in LinkedIn

COUNTERSELECTION. “If recombination has introduced maladaptive changes, eliminated niche-specific information, or disrupted coadapted alleles, then recombinant progeny will be counterselected. Therefore, ecological differentiation may impose a selective constraint on facile genetic exchange even in the absence of any mechanistic barriers imposed by the mismatch correction system.” https://lnkd.in/djKBnru View in LinkedIn

CASE STUDY. “If one chooses a group of closely related bacteria (e.g., the enterobacteria) and examines phylogenies of genes shared among them, many different genes may re-create the same phylogeny of species (even though recombination can destroy congruence of gene phylogenies within species).” https://lnkd.in/djKBnru View in LinkedIn

SELECTIVE ADVANTAGES. “Of course natural selection will act as the arbiter of success for all recombinant cells. That is, the evolutionary importance of recombinatorial events will depend on the probability that the products of gene exchange offer selective advantages.” https://lnkd.in/djKBnru View in LinkedIn

RADICAL WORKAROUNDS. “The evolution of a bacteriophage-type RNA polymerase functioning in mitochondria provides an example to show that drastic replacements in the transcription machinery can occur.” https://lnkd.in/djKBnru View in LinkedIn

RAPID CHANGE. “Yet these barriers, which change at a very rapid pace, are not correlated with the degree of overall sequence divergence; and they do not preclude DNA transfer but only limit the size of transferred fragments.” https://lnkd.in/djKBnru View in LinkedIn