Advances in epigenetics link genetics to the environment and disease

Nature Vol.571.25. 489-499

要旨

Epigeneticsの研究は、21世紀において急速に加速され、多くの興奮と希望を与えてくれるだろう。

この論説では、この研究分野がいかにして発展し、生物学の理解において大きな変革をもたらしたか

について述べる。特に、EpigeneticsDNA配列における変異との相互作用およびEpigenetics

による細胞の記憶や可塑性の重要性について考察する。さらに、環境要因による、その効果の世代内

および継世代的なepigenetic遺伝における効果について、生物学、疾患および進化について考察する。

最後に、epigeneticsのヒトの健康に対しての最新の知見を紹介する。

Fig. 1

Starting from the zygotic genome, stage- and cell-type-specific transcription factors initiate regulatory cascades that induce cell differentiation. Epigenetic components (for example, Polycomb PRC1/2 and Trithorax group proteins) maintain the ‘off’ states of certain genes and the ‘on’ states of others, in a cell-type- and time-specific manner (the bottom panels show three genes, depicted schematically as chromatinized templates, in which transcription is triggered by specific transcription factors and silent or active states are maintained by PRC1/2 or Trithorax proteins, respectively). In doing so, they constitute barriers against accidental reprogramming that maintain developmental and physiological homeostasis. Altered epigenomes can lead to changes in programmed cell differentiation or, when accidental, to disease (bottom right). Germline reprogramming resets the majority (but not all) of the epigenome to achieve reproduction (top right).

Table 1 Summary of the history and definitions of epigenetics

From: Advances in epigenetics link genetics to the environment and disease

AuthorsEpigenetics is the study of:References
Waddington the processes by which the genotype brings the phenotype into being 2
Nanney the systems that regulate the expression of the ‘library of specificities’ (that is, the genetic material, which is meant to be the DNA or RNA sequence) 4
Riggs, Holliday, Martienssen, Russo mitotically and/or meiotically heritable changes in gene function that cannot be explained by changes in DNA sequence 5, 151
Bird structural adaptations of chromosomal regions so as to register, signal or perpetuate altered activity states 8
Greally, Lappalainen properties of a cell, mediated by genomic regulators, that confer on the cell the ability to remember a past event. 59
Nicoglou various intracellular factors that have an effect on the stability of developmental processes through their action on genome potentialities 16

 

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