7 research outputs found
Inheritance of protection from osmotic stress
Exposure of mother worms to mild osmotic stress induces gene expression changes in offspring that protect them from strong osmotic stress. Inheritance of protection is now shown to depend on altered insulin-like signalling in the maternal germline, which confers protection through increased expression of zygotic gpdh-2, a rate-limiting enzyme in glycerol biosynthesis
The Barker hypothesis
The Barker hypothesis proposed that adverse nutrition in early life, including prenatally as measured by birth weight, increased susceptibility to the metabolic syndrome which includes obesity, diabetes, insulin insensitivity, hypertension, and hyperlipidemia and complications that include coronary heart disease and stroke. Periods of rapid postnatal growth associated with high-energy intake seem to be risk factors, along with a high-energy western diet. Theories proposing the mechanism of this association include the thrifty gene, bet-hedging, fetal predictive adaptive response, and drifty phenotype hypotheses. The cause of metabolic syndrome is likely to be multifactorial, with many nuclear DNA and cellular RNA sequences acting in concert with environmental influences. Epidemiological data in humans and experimental data indicate that transgenerational epigenetic inheritance is a possible mechanism where a history of starvation or deprivation during early life is seen in a grandparent and transgenerational effects are seen in their grandchildren. It remains to be seen whether this is mediated by heritable RNA sequences, or by acquired, possibly mosaic mutations in DNA coding for example for regulatory RNAs. Recent research has raised the possibility that the nature and quantity of gastrointestinal microorganisms (microbiota) can be modified by diet and conversely can modify an animal's metabolic program. As the microbiota is inherited largely from the mother, modification of her nutrition, health before and during pregnancy, and mode of delivery could influence the child's microbiota, introducing further potential avenues to improve the prevention, reduction of complications, and treatment of malnutrition and metabolic syndrome
Non-genomic transmission of longevity between generations: potential mechanisms and evidence across species
Evolution of plasticity in production and transgenerational inheritance of small RNAs under dynamic environmental conditions
The (not so) controversial role of DNA methylation in epigenetic inheritance across generations.
It has been demonstrated originally in plants that phenotypic traits,
such as floral symmetry, can be caused by changes of methylation
patterns of specific genes. Such traits can be transgenerationally
inherited for multiple generations and remain associated with cytosine
methylation patterns. Whether genomic methylation may also contribute to
epigenetic inheritance across generations in vertebrates and notably in
mammals is still more controversial. One reason for this tentativeness
is the dual occurrence of global genomic de-methylation first in
pre-implantation embryos and subsequently in primordial germ cells
(PGCs) of mammals. Although gene focused cases of epigenetic inheritance
associated with genomic DNA methylation have been well studied mostly
in rodents (such as imprinted genes and the Agouti viable yellow, Avy,
allele), it is still a matter of debate whether genomic DNA methylation
may provide a more general mechanism for the epigenetic inheritance of
acquired traits across generations. We review the current literature on
this topic with a focus on the potential role of DNA methylation for
epigenetic inheritance across generations in mammals