Functional HAK/KUP/KT-like potassium transporter encoded by chlorella viruses
Timo Greiner1, José Ramos, Maria C Alvarez
1Institute of Botany at the Technische Universität Darmstadt, Schnittspahnstrasse 3-5, 64287 Darmstadt, Germany.
The Plant Journal : for Cell and Molecular Biology
|August 19, 2011
Summary
Chlorella viruses encode a functional high-affinity K(+) transporter of chlorella virus (HAKCV). This viral transporter, expressed early during replication, does not substitute for viral K(+) channels.
Area of Science:
- Virology
- Molecular Biology
- Biochemistry
Background:
- Chlorella viruses possess unique membrane transport proteins.
- Investigating viral K(+) transporters provides insights into virus-host interactions.
Purpose of the Study:
- To characterize a putative K(+) transporter from chlorella virus FR483.
- To determine the function and expression of this viral transporter.
Main Methods:
- Yeast complementation assays.
- Rubidium-86 (Rb(+)) uptake experiments.
- Gene expression analysis and proteomics.
Main Results:
- The viral protein, HAKCV, functions as a high-affinity K(+) transporter.
- HAKCV shares similarities with plant, bacterial, and fungal K(+) transporters.
- HAKCV is an early viral gene product, not packaged in virions.
Conclusions:
- The identified viral K(+) transporter (HAKCV) is functional.
- HAKCV's role is not to replace viral K(+) channels during infection.
- The precise function of HAKCV in chlorella virus replication remains to be elucidated.
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