Article

Constitutive overexpression of a stress-inducible small GTP-binding protein PgRab7 from Pennisetum glaucum enhances abiotic stress tolerance in transgenic tobacco.

International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Road, New Delhi, 110 067, India.
Plant Cell Reports (impact factor: 2.27). 02/2008; 27(1):105-15. DOI:10.1007/s00299-007-0446-0 pp.105-15
Source: PubMed

ABSTRACT The Rab GTPases are important components of endocytic network in plant cells. Endocytosis participates in the cell's reaction to extracellular stimuli by desensitizing, down-regulating or recycling receptors and membrane proteins. Rab7 is a small GTP-binding protein involved in intracellular vesicle trafficking from late endosome to the vacuole. We have isolated Rab7 cDNA from Pennisetum glaucum, a relatively drought-stress tolerant food grain crop grown commonly in India, during cDNA-subtractive hybridization of dehydration-stress treated plants. The PgRab7 ORF, encoding 207 aminoacids, was over-expressed in E. coli. The recombinant PgRab7 protein showed GTP-binding and GTPase activity. Transcript expression of PgRab7 gene was differentially up-regulated by different environmental stimuli such as cold, dehydration and NaCl and also by a plant hormone IAA. Overexpression of PgRab7 gene enhanced tolerance to NaCl and mannitol in transgenic tobacco. Transgenic plants also had increased alkaline phosphatase (ALP) activity. These results show that PgRab7 is a potential candidate gene for developing both salinity and dehydration tolerance in planta.

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  • Article: Shotgun proteomic analysis of long-distance drought signaling in rice roots.
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    Journal of Proteome Research 11/2011; 11(1):348-58. · 5.11 Impact Factor
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Keywords

different environmental stimuli
 
drought-stress tolerant food grain crop
 
E. coli
 
encoding 207 aminoacids
 
extracellular stimuli
 
GTPase activity
 
intracellular vesicle trafficking
 
Pennisetum glaucum
 
PgRab7 gene
 
plant cells
 
plant hormone IAA
 
planta
 
potential candidate gene
 
Rab GTPases
 
Rab7 cDNA
 
recombinant PgRab7 protein
 
recycling receptors
 
small GTP-binding protein
 
Transgenic plants
 
transgenic tobacco
 

Pradeep K Agarwal