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Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
Functional analysis of OsPUT1, a rice polyamine uptake transporter
Vaishali Mulangi1, Vipaporn Phuntumart, Mustapha Aouida
1Department of Biological Sciences, Bowling Green State University, 442, Life Sciences Building, Bowling Green, OH, 43403-09, USA.
Planta
|July 29, 2011
Summary
Researchers identified the first plant polyamine transporter, OsPUT1, in rice. This spermidine-preferential transporter is crucial for polyamine transport and plant stress responses.
Area of Science:
- Plant Biology
- Molecular Biology
- Biochemistry
Background:
- Polyamines are vital for cell viability and regulate plant growth, development, and stress responses.
- Plant polyamine synthesis occurs in plastids and cytosol, necessitating specific transporters for intercellular movement.
Purpose of the Study:
- To identify and characterize novel polyamine transporters in rice using phylogenetic analysis.
- To elucidate the function and transport specificity of a candidate rice polyamine transporter.
Main Methods:
- Phylogenetic analysis to identify candidate transporters in rice.
- Heterologous expression of a rice cDNA clone (AK068055) in a yeast mutant (Saccharomyces cerevisiae agp2∆).
- Radiological uptake and competitive inhibition assays to determine transport specificity.
Main Results:
- The rice gene AK068055 encodes a protein, OsPUT1, functioning as a spermidine-preferential transporter.
- OsPUT1 transport activity was inhibited by methionine, asparagine, and glutamine.
- OsPUT1 is expressed in most rice tissues, excluding seeds and roots, and its cellular localization was undetermined.
Conclusions:
- OsPUT1 is the first characterized plant polyamine transporter, essential for polyamine transport.
- Understanding OsPUT1 function provides a foundation for modeling polyamine transport in plant development and stress responses.
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