DNA Loop-the-Loops

A new full-genome map indicates how DNA is folded within the nuclei of human cells.By Kate Yandell | December 11, 2014

Excerpt: “…many loops were conserved among cell types, and even between mice and humans. But others seemed to drive cell type-specific gene expression patterns.”

My comment to The Scientist Magazine:

Nutrient-dependent/pheromone-controlled adaptive evolution: a model. Excerpt: “A form of GnRH associated with sexual orientation in yeasts links control of the feedback loops and developmental processes required for nutrient acquisition, movement, reproduction, and the diversification of species from microbes to man [via RNA-directed DNA methylation and RNA-mediated amino acid substitutions that stabilize protein folding in the DNA of organized genomes].

I think this report on how DNA is folded within the nuclei of human cells makes it obvious that nutrient-dependent pheromone-controlled RNA-mediated amino acid substitutions, protein folding, and feedback loops link the epigenetic landscape to the physical landscape of DNA via what is currently known about the bio-physically constrained chemistry of protein folding and the conserved molecular mechanisms of cell type differentiation.

For cross species examples that include the honeybee model organism, see my 2012 and 2013 reviews, which are based on what we (T.B.) included in the molecular epigenetics section of our 1996 Hormones and Behavior review: From Fertilization to Adult Sexual Behavior  and on extension of RNA-mediated cell type differentiation to insects in Organizational and activational effects of hormones on insect behavior and to the life history transitions of honeybees in Honey bees as a model for understanding mechanisms of life history transitions.

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