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FEMALE LOSS OF LIFE STYLE. "Yet despite the apparent virtues of holometaboly, some insects have minimised or even lost the holometabolous lifestyle, at least from some part of the life cycle. With respect to holometabolous insects that have entirely lost complete metamorphosis, this has only occurred in females, where it has been achieved via the deletion of the pupal and post-metamorphic stage (i.e. the ancestral ‘adult’), via a developmental process known as paedomorphosis." http://onlinelibrary.wiley.com/doi/10.1111/een.12313/full View in LinkedIn

NEW THINKING. "This hypothesis, known as the duplication-degeneration-complementation (DDC) process, posits that degenerative mutations may knock out independent subfunctions encoded by discrete regulatory elements in duplicate genes, thus requiring preservation of both copies in order to maintain the full complement of ancestral gene functions." https://lnkd.in/eHCDVhZ View in LinkedIn

NEW TWIST. "Duplicate genes show evidence of purifying selection more consistent with buffering of the ancestral gene function than neofunctionalization reconciled Ohno's original theory with more recent observations by proposing subfunctionalization as a means of preserving duplicate genes in the presence of degenerative mutations targeting both members of a duplicate pair." https://lnkd.in/eHCDVhZ View in LinkedIn

POOR THEORETICAL FIT. "The preservation of large numbers of duplicate genes derived from ancient polyploidy events is difficult to reconcile with a model in which null alleles at duplicate loci are easily fixed by genetic drift." https://lnkd.in/eHCDVhZ View in LinkedIn

FATE OF GENES. "Seminal theory concerning the fates of duplicate genes predicted that the duplicate copy would be shielded from purifying selection by the ancestral copy, thus promoting pseudogenization in the absence of positive selection for a rare acquired function." https://lnkd.in/eHCDVhZ View in LinkedIn

EXAPTATION. "Notably, the processes of subfunctionalization and neofunctionalization may not be mutually exclusive. Indeed, the degenerative processes leading to subfunctionalization may act upon silencer elements and thereby promote neofunctionalization." https://lnkd.in/eHCDVhZ View in LinkedIn

GENE FATES AFTER DUPLICATION. "Following duplication, each gene within a paralogous pair may evolve in several ways. For example, it may retain the same set of functions as the ancestral copy, retain only a subset of the original set of functions (subfunctionalization), obtain a new function (neofunctionalization), or degrade into a nonfunctional gene (nonfunctionalization)." https://lnkd.in/eHCDVhZ View in LinkedIn

ENLARGED GENE FAMILIES. "Clusters of duplicated genes have also formed through tandem duplication (TD) processes, which have greatly expanded some gene families, such as the Nucleotide Binding Site-Leucine Rich Repeat (NBS-LRR) subset of plant resistance genes. Unequal recombination is thought to be the primary mechanism driving the expansion of these gene clusters." https://lnkd.in/eHCDVhZ View in LinkedIn

Inspired by nature: the thrilling new science that could transform medicine View in LinkedIn

EVOLUTION OF THE NUCLEUS. "One important event in early eukaryotic evolution was the development of a symbiotic relationship between the α-proteobacteria progenitor of mitochondria and an archaebacteria-like host. As with most endosymbiotically derived organelles, DNA was transferred from mitochondria to the host." http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1004351 View in LinkedIn