Overexpression of a Populus trichocarpa H+-pyrophosphatase gene PtVP1.1 confers salt tolerance on transgenic poplar.
Tree Physiol
; 35(6): 663-77, 2015 Jun.
Article
em En
| MEDLINE
| ID: mdl-25877769
ABSTRACT
The Arabidopsis vacuolar H(+)-pyrophosphatase (AVP1) has been well studied and subsequently employed to improve salt and/or drought resistance in herbaceous plants. However, the exact function of H(+)-pyrophosphatase in woody plants still remains unknown. In this work, we cloned a homolog of type I H(+)-pyrophosphatase gene, designated as PtVP1.1, from Populus trichocarpa, and investigated its function in both Arabidopsis and poplar. The deduced translation product PtVP1.1 shares 89.74% identity with AVP1. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time PCR analyses revealed a ubiquitous expression pattern of PtVP1.1 in various tissues, including roots, stems, leaves and shoot tips. Heterologous expression of PtVP1.1 rescued the retarded-root-growth phenotype of avp1, an Arabidopsis knock out mutant of AVP1, on low carbohydrate medium. Overexpression of PtVP1.1 in poplar (P. davidianaâ
×â
P. bolleana) led to more vigorous growth of transgenic plants in the presence of 150â
mM NaCl. Microsomal membrane vesicles derived from PtVP1.1 transgenic plants exhibited higher H(+)-pyrophosphatase hydrolytic activity than those from wild type (WT). Further studies indicated that the improved salt tolerance was associated with a decreased Na(+) and increased K(+) accumulation in the leaves of transgenic plants. Na(+) efflux and H(+) influx in the roots of transgenic plants were also significantly higher than those in the WT plants. All these results suggest that PtVP1.1 is a functional counterpart of AVP1 and can be genetically engineered for salt tolerance improvement in trees.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Adaptação Fisiológica
/
Cloreto de Sódio
/
Genes de Plantas
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Populus
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Pirofosfatase Inorgânica
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Tolerância ao Sal
Idioma:
En
Revista:
Tree Physiol
Assunto da revista:
BOTANICA
/
FISIOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article