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Analysis of the transgenerational iron deficiency stress memory in Arabidopsis thaliana plants.

Murgia I, Giacometti S, Balestrazzi A, Paparella S, Pagliano C, Morandini P - Front Plant Sci (2015)

Bottom Line: However, SHR frequency, DNA strand break events, and TFIIS-like gene expression do not increase further when plants are grown for more than one generation under the same stress, and furthermore, they decrease back to control values within two succeeding generations grown under control conditions, regardless of the Fe deficiency stress history of the mother plants.Lastly, plants grown for multiple generations under Fe deficiency produce seeds with greater longevity: however, this trait is not inherited in offspring generations unexposed to stress.These findings suggest the existence of multiple-step control of mechanisms to prevent a genuine and stable transgenerational transmission of Fe deficiency stress memory, with the tightest control on DNA integrity.

View Article: PubMed Central - PubMed

Affiliation: Department of Biosciences, University of Milano Milano, Italy.

ABSTRACT
We investigated the existence of the transgenerational memory of iron (Fe) deficiency stress, in Arabidopsis thaliana. Plants were grown under Fe deficiency/sufficiency, and so were their offspring. The frequency of somatic homologous recombination (SHR) events, of DNA strand breaks as well as the expression of the transcription elongation factor TFIIS-like gene increase when plants are grown under Fe deficiency. However, SHR frequency, DNA strand break events, and TFIIS-like gene expression do not increase further when plants are grown for more than one generation under the same stress, and furthermore, they decrease back to control values within two succeeding generations grown under control conditions, regardless of the Fe deficiency stress history of the mother plants. Seedlings produced from plants grown under Fe deficiency evolve more oxygen than control seedlings, when grown under Fe sufficiency: however, this trait is not associated with any change in the protein profile of the photosynthetic apparatus and is not transmitted to more than one generation. Lastly, plants grown for multiple generations under Fe deficiency produce seeds with greater longevity: however, this trait is not inherited in offspring generations unexposed to stress. These findings suggest the existence of multiple-step control of mechanisms to prevent a genuine and stable transgenerational transmission of Fe deficiency stress memory, with the tightest control on DNA integrity.

No MeSH data available.


Related in: MedlinePlus

Germination of A. thaliana seeds, produced from plants with transgenerational exposure to Fe deficiency. (A) Germination of c0 or pH 8.4 s1 Col seeds, after-ripened at room temperature for 3 months, or preserved at -20°C for 26–30 months. (B) Germination of c0, pH 7.7 s1, pH 7.7 s1 pH 7.7 s2, pH 7.7 s1 c2 Col seeds, after-ripened for 26–30 months at room temperature. As controls, c0 14.2 tAPX OE, 8.5 tAPX OE seeds after ripened for 26–30 months at room temperature as well as c0 Col seeds after-ripened for 6 years at room temperature were also used. Values correspond to mean percent germination ± SE from at least three plates containing 100 seeds each.
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Figure 7: Germination of A. thaliana seeds, produced from plants with transgenerational exposure to Fe deficiency. (A) Germination of c0 or pH 8.4 s1 Col seeds, after-ripened at room temperature for 3 months, or preserved at -20°C for 26–30 months. (B) Germination of c0, pH 7.7 s1, pH 7.7 s1 pH 7.7 s2, pH 7.7 s1 c2 Col seeds, after-ripened for 26–30 months at room temperature. As controls, c0 14.2 tAPX OE, 8.5 tAPX OE seeds after ripened for 26–30 months at room temperature as well as c0 Col seeds after-ripened for 6 years at room temperature were also used. Values correspond to mean percent germination ± SE from at least three plates containing 100 seeds each.

Mentions: As expected, young (3 months-old) after-ripened c0 or pH 8.4 s1 Col seeds all germinated within 2 days; full germination was also observed in older (26–30 months-old) c0 seeds, if stored at -20°C (Figure 7A). Next, germination of c0, pH 7.7 s1, pH 7.7 s1 pH 7.7 s2, pH 7.7 s1 c2 after-ripened 26–30 months Col seeds was measured. Germination of c0 Col seeds was below 50% (Figure 7B) and therefore much lower than that of same-age seeds stored at -20°C (Figure 7A). Germination of pH 7.7 s1 pH 7.7 s2 Col seeds was much higher, being above 80% (Figure 7B), whereas germination curves similar to control were observed in pH 7.7 s1 or pH 7.7 s1 c2 Col seeds (Figure 7B). Unfortunately, lack of 26–30 months after-ripened pH 7.7 s1 pH 7.7 s2 c3 Col seeds prevented us from further exploring longevity traits. Lastly, 26–30 months after-ripened c0 14.2 and 8.5 tAPX OE seeds (used as positive controls) showed 90–100% germination (Figure 7B), as high as that observed in young (3 months-old) after-ripened wt Col seeds, whereas fairly old c0 Col seeds (6 years after ripening) did not germinate (Figure 7B).


Analysis of the transgenerational iron deficiency stress memory in Arabidopsis thaliana plants.

Murgia I, Giacometti S, Balestrazzi A, Paparella S, Pagliano C, Morandini P - Front Plant Sci (2015)

Germination of A. thaliana seeds, produced from plants with transgenerational exposure to Fe deficiency. (A) Germination of c0 or pH 8.4 s1 Col seeds, after-ripened at room temperature for 3 months, or preserved at -20°C for 26–30 months. (B) Germination of c0, pH 7.7 s1, pH 7.7 s1 pH 7.7 s2, pH 7.7 s1 c2 Col seeds, after-ripened for 26–30 months at room temperature. As controls, c0 14.2 tAPX OE, 8.5 tAPX OE seeds after ripened for 26–30 months at room temperature as well as c0 Col seeds after-ripened for 6 years at room temperature were also used. Values correspond to mean percent germination ± SE from at least three plates containing 100 seeds each.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4585125&req=5

Figure 7: Germination of A. thaliana seeds, produced from plants with transgenerational exposure to Fe deficiency. (A) Germination of c0 or pH 8.4 s1 Col seeds, after-ripened at room temperature for 3 months, or preserved at -20°C for 26–30 months. (B) Germination of c0, pH 7.7 s1, pH 7.7 s1 pH 7.7 s2, pH 7.7 s1 c2 Col seeds, after-ripened for 26–30 months at room temperature. As controls, c0 14.2 tAPX OE, 8.5 tAPX OE seeds after ripened for 26–30 months at room temperature as well as c0 Col seeds after-ripened for 6 years at room temperature were also used. Values correspond to mean percent germination ± SE from at least three plates containing 100 seeds each.
Mentions: As expected, young (3 months-old) after-ripened c0 or pH 8.4 s1 Col seeds all germinated within 2 days; full germination was also observed in older (26–30 months-old) c0 seeds, if stored at -20°C (Figure 7A). Next, germination of c0, pH 7.7 s1, pH 7.7 s1 pH 7.7 s2, pH 7.7 s1 c2 after-ripened 26–30 months Col seeds was measured. Germination of c0 Col seeds was below 50% (Figure 7B) and therefore much lower than that of same-age seeds stored at -20°C (Figure 7A). Germination of pH 7.7 s1 pH 7.7 s2 Col seeds was much higher, being above 80% (Figure 7B), whereas germination curves similar to control were observed in pH 7.7 s1 or pH 7.7 s1 c2 Col seeds (Figure 7B). Unfortunately, lack of 26–30 months after-ripened pH 7.7 s1 pH 7.7 s2 c3 Col seeds prevented us from further exploring longevity traits. Lastly, 26–30 months after-ripened c0 14.2 and 8.5 tAPX OE seeds (used as positive controls) showed 90–100% germination (Figure 7B), as high as that observed in young (3 months-old) after-ripened wt Col seeds, whereas fairly old c0 Col seeds (6 years after ripening) did not germinate (Figure 7B).

Bottom Line: However, SHR frequency, DNA strand break events, and TFIIS-like gene expression do not increase further when plants are grown for more than one generation under the same stress, and furthermore, they decrease back to control values within two succeeding generations grown under control conditions, regardless of the Fe deficiency stress history of the mother plants.Lastly, plants grown for multiple generations under Fe deficiency produce seeds with greater longevity: however, this trait is not inherited in offspring generations unexposed to stress.These findings suggest the existence of multiple-step control of mechanisms to prevent a genuine and stable transgenerational transmission of Fe deficiency stress memory, with the tightest control on DNA integrity.

View Article: PubMed Central - PubMed

Affiliation: Department of Biosciences, University of Milano Milano, Italy.

ABSTRACT
We investigated the existence of the transgenerational memory of iron (Fe) deficiency stress, in Arabidopsis thaliana. Plants were grown under Fe deficiency/sufficiency, and so were their offspring. The frequency of somatic homologous recombination (SHR) events, of DNA strand breaks as well as the expression of the transcription elongation factor TFIIS-like gene increase when plants are grown under Fe deficiency. However, SHR frequency, DNA strand break events, and TFIIS-like gene expression do not increase further when plants are grown for more than one generation under the same stress, and furthermore, they decrease back to control values within two succeeding generations grown under control conditions, regardless of the Fe deficiency stress history of the mother plants. Seedlings produced from plants grown under Fe deficiency evolve more oxygen than control seedlings, when grown under Fe sufficiency: however, this trait is not associated with any change in the protein profile of the photosynthetic apparatus and is not transmitted to more than one generation. Lastly, plants grown for multiple generations under Fe deficiency produce seeds with greater longevity: however, this trait is not inherited in offspring generations unexposed to stress. These findings suggest the existence of multiple-step control of mechanisms to prevent a genuine and stable transgenerational transmission of Fe deficiency stress memory, with the tightest control on DNA integrity.

No MeSH data available.


Related in: MedlinePlus