Epigenetic factors regulate key signalling pathways in early body plan formation

Dynamic DNA methylation and demethylation crucial to regulation of key signalling pathways in early body plan formation


Excerpt: "Mammalian genomes undergo epigenetic modifications, including cytosine methylation by DNA methyltransferases (DNMTs). Oxidation of 5-methylcytosine by the Ten-eleven translocation (TET) family of dioxygenases can lead to demethylation. Although cytosine methylation has key roles in several processes such as genomic imprinting and X-chromosome inactivation, the functional significance of cytosine methylation and demethylation in mouse embryogenesis remains to be fully determined. Here a collaboration of researchers from China and the US show that inactivation of all three Tet genes in mice leads to gastrulation phenotypes, including primitive streak patterning defects in association with impaired maturation of axial mesoderm and failed specification of paraxial mesoderm, mimicking phenotypes in embryos with gain-of-function Nodal signalling.

...Taken together, their results show that TET-mediated oxidation of 5-methylcytosine modulates Lefty-Nodal signalling by promoting demethylation in opposition to methylation by DNMT3A and DNMT3B. These findings reveal a fundamental epigenetic mechanism featuring dynamic DNA methylation and demethylation crucial to regulation of key signalling pathways in early body plan formation."


My comment: Morphogenesis and body plan have long been difficult problems for molecular biology. Darwinists have claimed that gene sequences determine these very fundamental traits of organisms. They are wrong. Morphogenesis and body plan are both regulated by epigenetic factors. This is done at early stages of embryonic development. And because epigenetic markers are wiped out of embryonic cells   right after the fertilization, it's obvious that maternal and paternal short and long RNA molecules (siRNAs, miRNAs, piRNAs, lncRNAs) are in response of doing this job. Embryonic development occurs in control of maternal and paternal mechanisms of reproduction.

Gene sequences are not drivers. There is no such a thing as a mutation driven evolution. Genes are not your destiny. The evolutionary theory is a major lie. Don't get misled.

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