Limits...
Gene knockout study reveals that cytosolic ascorbate peroxidase 2(OsAPX2) plays a critical role in growth and reproduction in rice under drought, salt and cold stresses.

Zhang Z, Zhang Q, Wu J, Zheng X, Zheng S, Sun X, Qiu Q, Lu T - PLoS ONE (2013)

Bottom Line: Loss of function in OsAPX2 affected the growth and development of rice seedlings, resulting in semi-dwarf seedlings, yellow-green leaves, leaf lesion mimic and seed sterility.H2O2 and MDA levels were high in Osapx2 mutants but low in OsAPX2-OX transgenic lines relative to wild-type plants after stress treatments.Taken together, the cytosolic ascorbate peroxidase OsAPX2 plays an important role in rice growth and development by protecting the seedlings from abiotic stresses through scavenging reactive oxygen species.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Research Institute, Chinese Academy of Agricultural Sciences/National Key facility for Gene Resources And Genetic Improvement, Beijing, China.

ABSTRACT
Plant ascorbate peroxidases (APXs), enzymes catalyzing the dismutation of H2O2 into H2O and O2, play an important role in reactive oxygen species homeostasis in plants. The rice genome has eight OsAPXs, but their physiological functions remain to be determined. In this report, we studied the function of OsAPX2 gene using a T-DNA knockout mutant under the treatment of drought, salt and cold stresses. The Osapx2 knockout mutant was isolated by a genetic screening of a rice T-DNA insertion library under 20% PEG-2000 treatment. Loss of function in OsAPX2 affected the growth and development of rice seedlings, resulting in semi-dwarf seedlings, yellow-green leaves, leaf lesion mimic and seed sterility. OsAPX2 expression was developmental- and spatial-regulated, and was induced by drought, salt, and cold stresses. Osapx2 mutants had lower APX activity and were sensitive to abiotic stresses; overexpression of OsAPX2 increased APX activity and enhanced stress tolerance. H2O2 and MDA levels were high in Osapx2 mutants but low in OsAPX2-OX transgenic lines relative to wild-type plants after stress treatments. Taken together, the cytosolic ascorbate peroxidase OsAPX2 plays an important role in rice growth and development by protecting the seedlings from abiotic stresses through scavenging reactive oxygen species.

Show MeSH

Related in: MedlinePlus

Molecular analysis of Osapx2 mutants.A: Structure of OsAPX2 and the location of T-DNA insertion. Black boxes indicate protein-encoding exons. Arrows indicate the locations of PCR primers used. B: Confirmation of co-segregation of the T-DNA insertion with the PEG-sensitive and small seed phenotype in leaves of T1 heterozygous progeny. Two PEG-sensitive seedlings (Ho; Homo type), PCR-amplified product only from the P1-LB2 primer set (Osapx2/Osapx2); six normal seedlings (He; Hetero type), amplified with both the P1-LB2 and P1–P2 primer sets (Osapx2/OsAPX2); and seven normal seedlings (WT), which amplified only with the P1–P2 primer set (OsAPX2/OsAPX2). C: RT-PCR expression analysis in leaves of wild-type phenotype and PEG-sensitive mutant seedlings. Actin gene is used as control.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3585366&req=5

pone-0057472-g003: Molecular analysis of Osapx2 mutants.A: Structure of OsAPX2 and the location of T-DNA insertion. Black boxes indicate protein-encoding exons. Arrows indicate the locations of PCR primers used. B: Confirmation of co-segregation of the T-DNA insertion with the PEG-sensitive and small seed phenotype in leaves of T1 heterozygous progeny. Two PEG-sensitive seedlings (Ho; Homo type), PCR-amplified product only from the P1-LB2 primer set (Osapx2/Osapx2); six normal seedlings (He; Hetero type), amplified with both the P1-LB2 and P1–P2 primer sets (Osapx2/OsAPX2); and seven normal seedlings (WT), which amplified only with the P1–P2 primer set (OsAPX2/OsAPX2). C: RT-PCR expression analysis in leaves of wild-type phenotype and PEG-sensitive mutant seedlings. Actin gene is used as control.

Mentions: Genotyping of Osapx2 in T1 segregating population was performed by PCR using the following primers: P1 (5′-AACTTCCCATCCTCTCCTAC-3′), P2 (5′- CAAAGAAGGCGTCCTCATC-3′) and LB2 (5′-GTTCCTATAGGGTTTCGCTCATGTGTTG-3′) (Figure 3-A). More than 100 individual plants were analyzed. One µg of DNA was used as template with primers mixture (1 µM of P1, P2 and LB2, respectively) in a 20 ml reaction system. PCR was conducted with an initial step of 94°C incubation for 3 min and 30 cycles of 94°C for 30 s, 54°C for 30 s, and 72°C for 1 min.


Gene knockout study reveals that cytosolic ascorbate peroxidase 2(OsAPX2) plays a critical role in growth and reproduction in rice under drought, salt and cold stresses.

Zhang Z, Zhang Q, Wu J, Zheng X, Zheng S, Sun X, Qiu Q, Lu T - PLoS ONE (2013)

Molecular analysis of Osapx2 mutants.A: Structure of OsAPX2 and the location of T-DNA insertion. Black boxes indicate protein-encoding exons. Arrows indicate the locations of PCR primers used. B: Confirmation of co-segregation of the T-DNA insertion with the PEG-sensitive and small seed phenotype in leaves of T1 heterozygous progeny. Two PEG-sensitive seedlings (Ho; Homo type), PCR-amplified product only from the P1-LB2 primer set (Osapx2/Osapx2); six normal seedlings (He; Hetero type), amplified with both the P1-LB2 and P1–P2 primer sets (Osapx2/OsAPX2); and seven normal seedlings (WT), which amplified only with the P1–P2 primer set (OsAPX2/OsAPX2). C: RT-PCR expression analysis in leaves of wild-type phenotype and PEG-sensitive mutant seedlings. Actin gene is used as control.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3585366&req=5

pone-0057472-g003: Molecular analysis of Osapx2 mutants.A: Structure of OsAPX2 and the location of T-DNA insertion. Black boxes indicate protein-encoding exons. Arrows indicate the locations of PCR primers used. B: Confirmation of co-segregation of the T-DNA insertion with the PEG-sensitive and small seed phenotype in leaves of T1 heterozygous progeny. Two PEG-sensitive seedlings (Ho; Homo type), PCR-amplified product only from the P1-LB2 primer set (Osapx2/Osapx2); six normal seedlings (He; Hetero type), amplified with both the P1-LB2 and P1–P2 primer sets (Osapx2/OsAPX2); and seven normal seedlings (WT), which amplified only with the P1–P2 primer set (OsAPX2/OsAPX2). C: RT-PCR expression analysis in leaves of wild-type phenotype and PEG-sensitive mutant seedlings. Actin gene is used as control.
Mentions: Genotyping of Osapx2 in T1 segregating population was performed by PCR using the following primers: P1 (5′-AACTTCCCATCCTCTCCTAC-3′), P2 (5′- CAAAGAAGGCGTCCTCATC-3′) and LB2 (5′-GTTCCTATAGGGTTTCGCTCATGTGTTG-3′) (Figure 3-A). More than 100 individual plants were analyzed. One µg of DNA was used as template with primers mixture (1 µM of P1, P2 and LB2, respectively) in a 20 ml reaction system. PCR was conducted with an initial step of 94°C incubation for 3 min and 30 cycles of 94°C for 30 s, 54°C for 30 s, and 72°C for 1 min.

Bottom Line: Loss of function in OsAPX2 affected the growth and development of rice seedlings, resulting in semi-dwarf seedlings, yellow-green leaves, leaf lesion mimic and seed sterility.H2O2 and MDA levels were high in Osapx2 mutants but low in OsAPX2-OX transgenic lines relative to wild-type plants after stress treatments.Taken together, the cytosolic ascorbate peroxidase OsAPX2 plays an important role in rice growth and development by protecting the seedlings from abiotic stresses through scavenging reactive oxygen species.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Research Institute, Chinese Academy of Agricultural Sciences/National Key facility for Gene Resources And Genetic Improvement, Beijing, China.

ABSTRACT
Plant ascorbate peroxidases (APXs), enzymes catalyzing the dismutation of H2O2 into H2O and O2, play an important role in reactive oxygen species homeostasis in plants. The rice genome has eight OsAPXs, but their physiological functions remain to be determined. In this report, we studied the function of OsAPX2 gene using a T-DNA knockout mutant under the treatment of drought, salt and cold stresses. The Osapx2 knockout mutant was isolated by a genetic screening of a rice T-DNA insertion library under 20% PEG-2000 treatment. Loss of function in OsAPX2 affected the growth and development of rice seedlings, resulting in semi-dwarf seedlings, yellow-green leaves, leaf lesion mimic and seed sterility. OsAPX2 expression was developmental- and spatial-regulated, and was induced by drought, salt, and cold stresses. Osapx2 mutants had lower APX activity and were sensitive to abiotic stresses; overexpression of OsAPX2 increased APX activity and enhanced stress tolerance. H2O2 and MDA levels were high in Osapx2 mutants but low in OsAPX2-OX transgenic lines relative to wild-type plants after stress treatments. Taken together, the cytosolic ascorbate peroxidase OsAPX2 plays an important role in rice growth and development by protecting the seedlings from abiotic stresses through scavenging reactive oxygen species.

Show MeSH
Related in: MedlinePlus