Modeling epigenome dynamics: Polycomb

December 5, 2012 | James Kohl

Modeling of epigenome dynamics identifies transcription factors that mediate Polycomb targeting (2012) Arnold P, Schöler A, Pachkov M, Balwierz PJ, Jørgensen H, Stadler MB, van Nimwegen E, Schübeler D. Genome Res. Nov 20

Excerpt with my emphasis:

Here we use this approach to identify TFs that are involved in dynamic changes of a chromatin modification set by the Polycomb system, arguably the most relevant gene repression system during development (Schuettengruber and Cavalli 2009; Simon and Kingston 2009; Beisel and Paro 2011; Margueron and Reinberg 2011).

My comment: Note the publication dates on the cited articles above: 2009-2011, that attest to the relevance of the Polycomb system as included in our 1996 Hormones and Behavior review.

“Yet another kind of epigenetic imprinting occurs in species as diverse as yeast, Drosophila, mice, and humans and is based upon small DNA-binding proteins called “chromo domain” proteins, e.g., polycomb. These proteins affect chromatin structure, often in telomeric regions, and thereby affect transcription and silencing of various genes (Saunders, Chue, Goebl, Craig, Clark, Powers, Eissenberg, Elgin, Rothfield, and Earnshaw, 1993; Singh, Miller, Pearce, Kothary, Burton, Paro, James, and Gaunt, 1991; Trofatter, Long, Murrell, Stotler, Gusella, and Buckler, 1995). Small intranuclear proteins also participate in generating alternative splicing techniques of pre-mRNA and, by this mechanism, contribute to sexual differentiation in at least two species, Drosophila melanogaster and Caenorhabditis elegans (Adler and Hajduk, 1994; de Bono, Zarkower, and Hodgkin, 1995; Ge, Zuo, and Manley, 1991; Green, 1991; Parkhurst and Meneely, 1994; Wilkins, 1995; Wolfner, 1988). That similar proteins perform functions in humans suggests the possibility that some human sex differences may arise from alternative splicings of otherwise identical genes.”

The time lapse from research we cited in the early 90’s to research now cited from 2009-2011 indicate that others were ignoring our works. Were they simply waiting to build their reputations until past efforts to focus attention on what now seems to be the most relevant gene repression system during development were forgotten? We may never know.  We do know,  however, that some academics care more about reputation than science, and about appearing to be knowledgeable more than actually being knowledgeable. They will only give credit when forced to do so, or when it is politically expedient.

Follow up: Thus, O-GlcNAc cycling may serve as a homeostatic mechanism linking nutrient availability to higher-order chromatin organization. In response to nutrient availability, O-GlcNAcylation is poised to influence X chromosome inactivation and genetic imprinting, as well as embryonic development.




James Vaughn Kohl

James Vaughn Kohl

James Vaughn Kohl was the first to accurately conceptualize human pheromones, and began presenting his findings to the scientific community in 1992. He continues to present to, and publish for, diverse scientific and lay audiences, while constantly monitoring the scientific presses for new information that is relevant to the development of his initial and ongoing conceptualization of human pheromones.