Limits...
Overexpression of an ABA biosynthesis gene using a stress-inducible promoter enhances drought resistance in petunia.

Estrada-Melo AC - Hortic Res (2015)

Bottom Line: The response of plants to drought stress includes reduced transpiration as stomates close in response to increased abscisic acid (ABA) concentrations.Constitutive overexpression of 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, increases drought resistance, but causes negative pleiotropic effects on plant growth and development.Well-watered transgenic plants grew like non-transformed control plants and there was no effect of the transgene on seed dormancy.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Sciences, University of California Davis , Davis, CA, USA.

ABSTRACT
The response of plants to drought stress includes reduced transpiration as stomates close in response to increased abscisic acid (ABA) concentrations. Constitutive overexpression of 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, increases drought resistance, but causes negative pleiotropic effects on plant growth and development. We overexpressed the tomato NCED (LeNCED1) in petunia plants under the control of a stress-inducible promoter, rd29A. Under water stress, the transgenic plants had increased transcripts of NCED mRNA, elevated leaf ABA concentrations, increased concentrations of proline, and a significant increase in drought resistance. The transgenic plants also displayed the expected decreases in stomatal conductance, transpiration, and photosynthesis. After 14 days without water, the control plants were dead, but the transgenic plants, though wilted, recovered fully when re-watered. Well-watered transgenic plants grew like non-transformed control plants and there was no effect of the transgene on seed dormancy.

No MeSH data available.


Related in: MedlinePlus

LeNCED1 expression and ABA content in LeNCED1-overexpressed petunia. Plants of non-transformed control, transgenic rd29A:LeNCED1 lines 8F, 7D, 3D, and CaMV-35S:LeNCED1-12F line were grown in UC mix soils in greenhouse for 6 weeks under non-stress conditions and were subjected to drought treatment by withholding irrigation for 3 days. Transcript abundances of the LeNCED1 were determined with semi-quantitative RT-PCR using intact leaves after 0- and 3-day drought treatment (a, b). Error bars show SE of the means of three biological replicates; different letters denote significant differences using t-test at P > 0.05. ABA contents were measured using ELISA methods as described in M & M (c). Leaf samples were taken from the non-transformed control, transgenic rd29A:LeNCED1 and CaMV-35S:LeNCED1 lines at 0 and 3 days after drought treatment. Data are means ± SD (n = 6). Different letters denote significant differences at the 0.05 level.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4595983&req=5

fig5: LeNCED1 expression and ABA content in LeNCED1-overexpressed petunia. Plants of non-transformed control, transgenic rd29A:LeNCED1 lines 8F, 7D, 3D, and CaMV-35S:LeNCED1-12F line were grown in UC mix soils in greenhouse for 6 weeks under non-stress conditions and were subjected to drought treatment by withholding irrigation for 3 days. Transcript abundances of the LeNCED1 were determined with semi-quantitative RT-PCR using intact leaves after 0- and 3-day drought treatment (a, b). Error bars show SE of the means of three biological replicates; different letters denote significant differences using t-test at P > 0.05. ABA contents were measured using ELISA methods as described in M & M (c). Leaf samples were taken from the non-transformed control, transgenic rd29A:LeNCED1 and CaMV-35S:LeNCED1 lines at 0 and 3 days after drought treatment. Data are means ± SD (n = 6). Different letters denote significant differences at the 0.05 level.

Mentions: LeNCED1 transcripts could not be detected in non-stressed leaves from the three rd29A:LeNCED1 transgenic lines (0 h) but were abundant in leaves from the CaMV-35S:LeNCED1 line (Figure 5a). After 3 days of drought, LeNCED1 transcript abundance had increased dramatically in leaves from the three rd29A:LeNCED1 transgenic lines and was similar to that in the CaMV-35S:LeNCED1 transgenic plants (Figure 5a).


Overexpression of an ABA biosynthesis gene using a stress-inducible promoter enhances drought resistance in petunia.

Estrada-Melo AC - Hortic Res (2015)

LeNCED1 expression and ABA content in LeNCED1-overexpressed petunia. Plants of non-transformed control, transgenic rd29A:LeNCED1 lines 8F, 7D, 3D, and CaMV-35S:LeNCED1-12F line were grown in UC mix soils in greenhouse for 6 weeks under non-stress conditions and were subjected to drought treatment by withholding irrigation for 3 days. Transcript abundances of the LeNCED1 were determined with semi-quantitative RT-PCR using intact leaves after 0- and 3-day drought treatment (a, b). Error bars show SE of the means of three biological replicates; different letters denote significant differences using t-test at P > 0.05. ABA contents were measured using ELISA methods as described in M & M (c). Leaf samples were taken from the non-transformed control, transgenic rd29A:LeNCED1 and CaMV-35S:LeNCED1 lines at 0 and 3 days after drought treatment. Data are means ± SD (n = 6). Different letters denote significant differences at the 0.05 level.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4595983&req=5

fig5: LeNCED1 expression and ABA content in LeNCED1-overexpressed petunia. Plants of non-transformed control, transgenic rd29A:LeNCED1 lines 8F, 7D, 3D, and CaMV-35S:LeNCED1-12F line were grown in UC mix soils in greenhouse for 6 weeks under non-stress conditions and were subjected to drought treatment by withholding irrigation for 3 days. Transcript abundances of the LeNCED1 were determined with semi-quantitative RT-PCR using intact leaves after 0- and 3-day drought treatment (a, b). Error bars show SE of the means of three biological replicates; different letters denote significant differences using t-test at P > 0.05. ABA contents were measured using ELISA methods as described in M & M (c). Leaf samples were taken from the non-transformed control, transgenic rd29A:LeNCED1 and CaMV-35S:LeNCED1 lines at 0 and 3 days after drought treatment. Data are means ± SD (n = 6). Different letters denote significant differences at the 0.05 level.
Mentions: LeNCED1 transcripts could not be detected in non-stressed leaves from the three rd29A:LeNCED1 transgenic lines (0 h) but were abundant in leaves from the CaMV-35S:LeNCED1 line (Figure 5a). After 3 days of drought, LeNCED1 transcript abundance had increased dramatically in leaves from the three rd29A:LeNCED1 transgenic lines and was similar to that in the CaMV-35S:LeNCED1 transgenic plants (Figure 5a).

Bottom Line: The response of plants to drought stress includes reduced transpiration as stomates close in response to increased abscisic acid (ABA) concentrations.Constitutive overexpression of 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, increases drought resistance, but causes negative pleiotropic effects on plant growth and development.Well-watered transgenic plants grew like non-transformed control plants and there was no effect of the transgene on seed dormancy.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Sciences, University of California Davis , Davis, CA, USA.

ABSTRACT
The response of plants to drought stress includes reduced transpiration as stomates close in response to increased abscisic acid (ABA) concentrations. Constitutive overexpression of 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, increases drought resistance, but causes negative pleiotropic effects on plant growth and development. We overexpressed the tomato NCED (LeNCED1) in petunia plants under the control of a stress-inducible promoter, rd29A. Under water stress, the transgenic plants had increased transcripts of NCED mRNA, elevated leaf ABA concentrations, increased concentrations of proline, and a significant increase in drought resistance. The transgenic plants also displayed the expected decreases in stomatal conductance, transpiration, and photosynthesis. After 14 days without water, the control plants were dead, but the transgenic plants, though wilted, recovered fully when re-watered. Well-watered transgenic plants grew like non-transformed control plants and there was no effect of the transgene on seed dormancy.

No MeSH data available.


Related in: MedlinePlus