Month: September 2022

WEISMANN'S DOCTRINE. "The principle, proposed by A. Weismann, that hereditary information flows only from genome to soma, not vice versa; the principle would be flouted were Lamarckism true. In its refined, modern form, the principle reads that information flows always from DNA to RNA to protein, and not back again.” https://lnkd.in/e5fymDv View in LinkedIn

SOMATIC MUTATIONS. "The influence of somatic mutations on fitness is relevant in plants because of their indeterminate growth and lack of separation between somatic and germ-line tissues, thus violating Weismann’s doctrine. The frequency of somatic mutation should be correlated with the number of mitotic divisions between zygote formation and gamete production." http://www.pnas.org/content/112/29/8859.full View in LinkedIn

WEISMANN CHALLENGED. “An enzyme, reverse transcriptase, is now known that does allow information to flow from RNA to DNA, and a category of viruses (retroviruses) do insert their genetic component into their hosts' DNA by this means. Some genes (virogenes) appear to be of viral origin. http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/weismanns-doctrine View in LinkedIn

Free school fruit contains multiple pesticides, report shows. Little and often. https://www.theguardian.com/environment/2017/sep/05/free-school-fruit-contains-multiple-pesticides-report-shows?CMP=Share_iOSApp_Other View in LinkedIn

BENEFICIAL MOSAICS. "The great size and longevity of many trees and clonal plants is predicted to be associated with the accumulation of numerous somatic mutations in cell lineages. Some have argued for the adaptive benefits of this type of variation because of the formation of genetic mosaics and their role in plant defense." http://www.pnas.org/content/112/29/8859.full View in LinkedIn

ACCUMULATED MUTATIONS. "However, in most cases, the gradual accumulation of deleterious mutations during growth is more likely to negatively influence fitness because these mutations can be potentially transmitted from shoot meristems to gametes when flowering occurs. As long as somatic mutations do not limit clonal growth, they should accumulate over the life span of genets." http://www.pnas.org/content/112/29/8859.full View in LinkedIn

LITTLE DIVERSITY. "Many clonal species are highly successful plant invaders, and, in some cases, their populations seem to contain little if any genetic diversity." http://www.pnas.org/content/112/29/8859.full View in LinkedIn

PHENOTYPIC COMPENSATION. In clonal plants lacking genetic diversity, "phenotypic plasticity is thought to play a major role in enabling populations to cope with environmental heterogeneity." http://www.pnas.org/content/112/29/8859.full View in LinkedIn

TO BE DETERMINED. "Phenotypic plasticity may not be the only mechanism enabling clonal invaders to colonize widely, and the role of somatic mutations and epigenetic variation would be worth investigating in the future." http://www.pnas.org/content/112/29/8859.full View in LinkedIn

"APOMIXIS is the clonal production of a plant through seed. It is a naturally occurring trait that has been studied for many years but the tools necessary to dissect it at the molecular level have been available only recently." https://lnkd.in/dXcGB3t View in LinkedIn