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Unexplored potentials of epigenetic mechanisms of plants and animals-theoretical considerations.

Seffer I, Nemeth Z, Hoffmann G, Matics R, Seffer AG, Koller A - Genet Epigenet (2013)

Bottom Line: Genes are regulated-in part-by epigenetic mechanisms resulting in alternating patterns of gene expressions throughout life.Epigenetic changes responding to the environmental and intercellular signals can turn on/off specific genes, but do not modify the DNA sequence.Finally, we hypothesize that animal genome can be reprogrammed by epigenetic factors from the plant protoplast.

View Article: PubMed Central - PubMed

Affiliation: Seffer-Renner Medical Clinic, Budapest, Hungary.

ABSTRACT
Morphological and functional changes of cells are important for adapting to environmental changes and associated with continuous regulation of gene expressions. Genes are regulated-in part-by epigenetic mechanisms resulting in alternating patterns of gene expressions throughout life. Epigenetic changes responding to the environmental and intercellular signals can turn on/off specific genes, but do not modify the DNA sequence. Most epigenetic mechanisms are evolutionary conserved in eukaryotic organisms, and several homologs of epigenetic factors are present in plants and animals. Moreover, in vitro studies suggest that the plant cytoplasm is able to induce a nuclear reassembly of the animal cell, whereas others suggest that the ooplasm is able to induce condensation of plant chromatin. Here, we provide an overview of the main epigenetic mechanisms regulating gene expression and discuss fundamental epigenetic mechanisms and factors functioning in both plants and animals. Finally, we hypothesize that animal genome can be reprogrammed by epigenetic factors from the plant protoplast.

No MeSH data available.


Related in: MedlinePlus

Changes in cellular plasticity. (A) Gene silencing and activation during differentiation and dedifferentiation. In a totipotent cell, such as the fertilized egg, genes responsible for segmentation and formation of pluripotent embryonic cells are switched on. Throughout differentiation, early genes are switched off, while genes needed for differentiated cell functions are switched on and others are switched off or repressed. Repressed genes can be activated reprogramming somatic cells, eg, neuron to totipotent or pluripotent states. (B) Epigenetic modifications or cell plasticity enables stem cells to differentiate into various cell types or differentiated cells to trans-differentiate to each other. During differentiation, cell plasticity is decreased. Differentiated cells have low plasticity; however, high plasticity can be increased by adding extrinsic factors that affect epigenetic processes, even in completely differentiated cells.
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f2-geg-5-2013-023: Changes in cellular plasticity. (A) Gene silencing and activation during differentiation and dedifferentiation. In a totipotent cell, such as the fertilized egg, genes responsible for segmentation and formation of pluripotent embryonic cells are switched on. Throughout differentiation, early genes are switched off, while genes needed for differentiated cell functions are switched on and others are switched off or repressed. Repressed genes can be activated reprogramming somatic cells, eg, neuron to totipotent or pluripotent states. (B) Epigenetic modifications or cell plasticity enables stem cells to differentiate into various cell types or differentiated cells to trans-differentiate to each other. During differentiation, cell plasticity is decreased. Differentiated cells have low plasticity; however, high plasticity can be increased by adding extrinsic factors that affect epigenetic processes, even in completely differentiated cells.

Mentions: The importance of the discovery by Gurdon130 that specialization of cells is reversible and by Shinya Yamanaka128 that intact mature cells can be reprogrammed to become immature stem cells is acclaimed by award of Nobel Prize in Physiology or Medicine in 2012. Notably, there is a great difference between the cellular plasticity of plants and animals. Cellular plasticity is the ability of cells to change their structure or function to become a different type of cell is, as we understand today, depending on the epigenetic regulation of gene expression (Fig. 2). Plasticity of plant cells to transdifferentiate into various types of cells is much higher than that of animal cells, which implies a much “looser” chromatin structure. This, however, should not be interpreted that the chromatin structure is less complex or that it is more complicated to regulate.131,132 Further in vitro epigenetic experiments and in vivo experiments, such as xeno-transplantation, may reveal this phenomenon. Based on experimental results, it may be possible to reprogram a fully differentiated animal cell nucleus using a recipient plant protoplast, a hypothesis which should be verified by future research.


Unexplored potentials of epigenetic mechanisms of plants and animals-theoretical considerations.

Seffer I, Nemeth Z, Hoffmann G, Matics R, Seffer AG, Koller A - Genet Epigenet (2013)

Changes in cellular plasticity. (A) Gene silencing and activation during differentiation and dedifferentiation. In a totipotent cell, such as the fertilized egg, genes responsible for segmentation and formation of pluripotent embryonic cells are switched on. Throughout differentiation, early genes are switched off, while genes needed for differentiated cell functions are switched on and others are switched off or repressed. Repressed genes can be activated reprogramming somatic cells, eg, neuron to totipotent or pluripotent states. (B) Epigenetic modifications or cell plasticity enables stem cells to differentiate into various cell types or differentiated cells to trans-differentiate to each other. During differentiation, cell plasticity is decreased. Differentiated cells have low plasticity; however, high plasticity can be increased by adding extrinsic factors that affect epigenetic processes, even in completely differentiated cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4222336&req=5

f2-geg-5-2013-023: Changes in cellular plasticity. (A) Gene silencing and activation during differentiation and dedifferentiation. In a totipotent cell, such as the fertilized egg, genes responsible for segmentation and formation of pluripotent embryonic cells are switched on. Throughout differentiation, early genes are switched off, while genes needed for differentiated cell functions are switched on and others are switched off or repressed. Repressed genes can be activated reprogramming somatic cells, eg, neuron to totipotent or pluripotent states. (B) Epigenetic modifications or cell plasticity enables stem cells to differentiate into various cell types or differentiated cells to trans-differentiate to each other. During differentiation, cell plasticity is decreased. Differentiated cells have low plasticity; however, high plasticity can be increased by adding extrinsic factors that affect epigenetic processes, even in completely differentiated cells.
Mentions: The importance of the discovery by Gurdon130 that specialization of cells is reversible and by Shinya Yamanaka128 that intact mature cells can be reprogrammed to become immature stem cells is acclaimed by award of Nobel Prize in Physiology or Medicine in 2012. Notably, there is a great difference between the cellular plasticity of plants and animals. Cellular plasticity is the ability of cells to change their structure or function to become a different type of cell is, as we understand today, depending on the epigenetic regulation of gene expression (Fig. 2). Plasticity of plant cells to transdifferentiate into various types of cells is much higher than that of animal cells, which implies a much “looser” chromatin structure. This, however, should not be interpreted that the chromatin structure is less complex or that it is more complicated to regulate.131,132 Further in vitro epigenetic experiments and in vivo experiments, such as xeno-transplantation, may reveal this phenomenon. Based on experimental results, it may be possible to reprogram a fully differentiated animal cell nucleus using a recipient plant protoplast, a hypothesis which should be verified by future research.

Bottom Line: Genes are regulated-in part-by epigenetic mechanisms resulting in alternating patterns of gene expressions throughout life.Epigenetic changes responding to the environmental and intercellular signals can turn on/off specific genes, but do not modify the DNA sequence.Finally, we hypothesize that animal genome can be reprogrammed by epigenetic factors from the plant protoplast.

View Article: PubMed Central - PubMed

Affiliation: Seffer-Renner Medical Clinic, Budapest, Hungary.

ABSTRACT
Morphological and functional changes of cells are important for adapting to environmental changes and associated with continuous regulation of gene expressions. Genes are regulated-in part-by epigenetic mechanisms resulting in alternating patterns of gene expressions throughout life. Epigenetic changes responding to the environmental and intercellular signals can turn on/off specific genes, but do not modify the DNA sequence. Most epigenetic mechanisms are evolutionary conserved in eukaryotic organisms, and several homologs of epigenetic factors are present in plants and animals. Moreover, in vitro studies suggest that the plant cytoplasm is able to induce a nuclear reassembly of the animal cell, whereas others suggest that the ooplasm is able to induce condensation of plant chromatin. Here, we provide an overview of the main epigenetic mechanisms regulating gene expression and discuss fundamental epigenetic mechanisms and factors functioning in both plants and animals. Finally, we hypothesize that animal genome can be reprogrammed by epigenetic factors from the plant protoplast.

No MeSH data available.


Related in: MedlinePlus