FROM VACUOLAR GS-X PUMPS TO MULTISPECIFIC ABC TRANSPORTERS
Philip A. Rea1, Ze-Sheng Li, Yu-Ping Lu
1Plant Science Institute, Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104; e-mail: parea@sas.upenn.edu, Institut de Botanique, Universite de Neuchatel, 2007 Neuchatel, Switzerland
Annual Review of Plant Physiology and Plant Molecular Biology
|March 12, 2004
Summary
Plant ABC transporters, specifically multidrug resistance-associated proteins (MRPs), utilize MgATP for solute transport, offering new insights into plant processes like herbicide detoxification and pigment storage.
Area of Science:
- Plant molecular biology
- Biochemistry
- Cellular transport
Background:
- H+-coupling has long dominated plant solute transport research.
- ATP-binding cassette (ABC) superfamily transporters are energized by MgATP.
- Plant ABC transporters include multidrug resistance-associated proteins (MRPs) and multidrug resistance proteins (MDRs).
Purpose of the Study:
- To review the functional capabilities, energetics, organization, and regulation of plant MRPs.
- To highlight the role of MRPs in transporting anions and glutathionated compounds.
- To explore the broader implications of ABC transporters in plant physiology.
Main Methods:
- Literature review focusing on functional studies of plant MRPs.
- Analysis of the known structure and subclasses of ABC transporters in plants.
- Synthesis of current understanding of MRP energetics and substrate specificity.
Main Results:
- Plant MRPs, also known as GS-X pumps, transport amphipathic anions and glutathionated compounds from cytosol to vacuole.
- MRPs are involved in herbicide detoxification, pigmentation, oxidative stress alleviation, and storage of antimicrobial compounds.
- ABC transporters play a central role in various fundamental plant processes.
Conclusions:
- Plant MRPs represent a distinct class of energy-dependent transporters.
- ABC transporters are crucial for diverse physiological functions in plants.
- Understanding MRPs offers potential for manipulating plant processes at the transport level.
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