Transporter Specificity: A Tale of Loosened Elevator-Sliding
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Updated: Nov 8, 2025

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Published on: November 3, 2010
1Department of Biology, National and Kapodistrian University of Athens, Panepistimioupolis, 15784, Athens, Greece; Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion, Greece.
Abstract:
Elevator-type transporters are a group of proteins translocating nutrients and metabolites across cell membranes. Despite structural and functional differences, elevator-type transporters use a common mechanism of substrate translocation via reversible movements of a mobile core domain (the elevator), which includes the substrate binding site, along a rigid scaffold domain, stably anchored in the plasma membrane. How substrate specificity is determined in elevator transporters remains elusive. Here, I discuss how a recent report on the sliding elevator mechanism, seen under the context of genetic analysis of a prototype fungal transporter, sheds light on how specificity might be genetically modified. I propose that flexible specificity alterations might occur by 'loosening' of the sliding mechanism from tight coupling to substrate binding.
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