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Rare earth elements (REEs) have become increasingly important materials owing to their use in the high‐tech and clean‐energy industries. However, the unpredictable supply, possible health risks, and environmentally unsustainable extraction practices associated with REEs have encouraged the development of green technologies for the selective extraction and recovery of metals. This study presents a simple and innovative approach for the selective extraction and recovery of total REEs. Elastin‐like polypeptide (ELP) and the REE‐binding domain (lanmodulin) are fused to form REEs‐sensitive and thermo‐responsive genetically encoded ELP called RELP, where ELP offered a reversible, inverse phase transition for repeated uses. The RELP are purified and used for the selective extraction of total REEs from competing non‐REEs metals by controlling the solution temperature (4 and 37 °C) and pH. RELP exhibit high REE specificity, even in the presence of non‐REE metal ions. The bound REEs are readily recovered during at least six repeated cycles, and the efficiency is maintained. Moreover, REEs are selectively recovered by RELP from steel slag leachate, a potential industrial source of REEs. RELP offers a rapid, selective, and scalable method for REE extraction and recovery. This technology can be adapted to recover other precious metals and commodities. [ABSTRACT FROM AUTHOR]

A ubiquitous approach to studying protein function is to knock down activity (gene deletions, siRNA, small molecule inhibitors, etc.) and to study the cellular effects. Using a new methodology, this article describes how to rapidly and specifically switch off cellular pathways using thermally responsive protein polymers. A small increase in temperature stimulates cytosolic elastin-like polypeptides (ELPs) to assemble microdomains. It is hypothesized that ELPs fused to a key effector in a target macromolecular complex will sequester the complex within these microdomains, which will bring the pathway to a halt. To test this hypothesis, ELPs are fused to clathrin-light chain (CLC), a protein associated with clathrin-mediated endocytosis. Prior to thermal stimulation, the ELP fusion is soluble and clathrin-mediated endocytosis remains 'on'. Increasing the temperature induces the assembly of ELP fusion proteins into organelle-sized microdomains that switches clathrin-mediated endocytosis 'off'. These microdomains can be thermally activated and inactivated within minutes, are reversible, do not require exogenous chemical stimulation, and are specific for components trafficked within the clathrin-mediated endocytosis pathway. This temperature-triggered cell switch system represents a new platform for the temporal manipulation of trafficking mechanisms in normal and disease cell models and has applications for manipulating other intracellular pathways. [ABSTRACT FROM AUTHOR]

Elastin‐like polypeptides can be expressed in eukaryotic cells in fusion with functional proteins. When heated, they assemble organelle‐sized microdomains that sequester target complexes. On page 5340, J. A. MacKay and team demonstrate that, by fusion to clathrin‐light chain, these microdomains co‐localize and sequester clathrin heavy chain, which is necessary for clathrin‐mediated endocytosis. Assembly rapidly and reversibly blocks internalization of G‐protein coupled receptors. Image created by Isaac Mora. [ABSTRACT FROM AUTHOR]