In Situ Self-Sorting Peptide Assemblies in Living Cells for Simultaneous Organelle Targeting

Abstract

Self-sorting is a common phenomenon in eukaryotic cells and represents one of the versatile strategies for the formation of advanced functional materials; however, developing artificial self-sorting assemblies within living cells remains challenging. Here, we report on the GSHresponsive in situ self-sorting peptide assemblies within cancer cells for simultaneous organelle targeting to promote combinatorial organelle dysfunction and thereby cell death. The self-sorting system was created via the design of two peptides E3C16E6 and EVM SeO derived from lipidinspired peptide interdigitating amphiphiles and peptide bola-amphiphiles, respectively. The distinct organization patterns of the two peptides facilitate their GSH-induced self-sorting into isolated nanofibrils as a result of cleavage of disulfide-connected hydrophilic domains or reduction of selenoxide groups. The GSH-responsive in situ self-sorting in the peptide assemblies within HeLa cells was directly characterized by super-resolution structured illumination microscopy. Incorporation of the thiol and ER-targeting groups into the self-sorted assemblies endows their simultaneous targeting of endoplasmic reticulum and Golgi apparatus, thus leading to combinatorial organelle dysfunction and cell death. Our results demonstrate the establishment of the in situ self-sorting peptide assemblies within living cells, thus providing a unique platform for drug targeting delivery and an alternative strategy for modulating biological processes in the future.

Stimulus‐Responsive Amino Acids Behind In Situ Assembled Bioactive Peptide Materials

“…In this context, our group has developed a GSH‐responsive intracellular in situ self‐sorting peptide assembling system with simultaneous targeting function towards endoplasmic reticulum and Golgi apparatus (Figure 5). [41] The in situ self‐sorting systems consist of two GSH‐responsive assembling peptides organized in a distinct manner, i. e. E3C16E6 and EVM SeO , which are derived from lipid‐inspired peptide interdigitating amphiphiles and bola‐amphiphiles, respectively. After GSH‐induced reduction of disulfide bonds and selenoxide groups, E3C16E6 and EVM SeO independently assembled into twisted or flat nanoribbons, thus leading to the self‐sorting system.…”

“…Acid-base [58] Acid-base [58] Acid-base [36] Isomerization [39] Cleavage [59] Redox-responsive Redox [60] Cleavage [61] Redox [47] Redox [41] Enzyme-responsive Cleavage [62] Redox [38] Cleavage [63] Photo-responsive Cleavage [64] microenvironment. [82] The cleaved bonds mostly are not reformed and thus leading to irreversible pH-responsive selfassembly of peptides.…”

“…Hence, various stimulus‐responsive reactions including protonation, cleavage, cross‐linking, redox, and isomerization promoted by enzyme, [32] photon, [33] ROS, [17,34] GSH, [35] or acid [36] have been developed to enhance or reduce the interacting intensity of peptides. In this context, incorporation of srAAs allows for establishment of controllable peptide assembling systems on the basis of activatable reactions occurring on srAAs, as exemplified by enzyme‐responsive phosphorylated tyrosine [37] and 2‐nitroimidazolyl alanine, [38] acid‐responsive 4‐aminoproline, [39,40] and redox‐responsive seleno‐methionine [41] . Over the past decade, controllable self‐assembly of peptides regulated by the stimuli‐responsiveness of amino acids have shown the great potential in formation of nanostructures with diagnostic or therapeutic activity in living systems.…”

“…In this context, incorporation of srAAs allows for establishment of controllable peptide assembling systems on the basis of activatable reactions occurring on srAAs, as exemplified by enzyme-responsive phosphorylated tyrosine [37] and 2-nitroimidazolyl alanine, [38] acid-responsive 4-aminoproline, [39,40] and redox-responsive seleno-methionine. [41] Over the past decade, controllable self-assembly of peptides regulated by the stimuliresponsiveness of amino acids have shown the great potential in formation of nanostructures with diagnostic or therapeutic activity in living systems.…”

Surfactant-Assisted Assembly of Dipeptide Forming a Broom-like Structure

“…The behavior of peptides, which can self-assemble into various nanostructures, has attracted much attention because of their applications in biomedical, bioengineering and drug production [ 4 , 5 , 6 , 7 , 8 ]. In contrast to other supramolecular structural motifs, the unique and desirable features of peptides include their chemical diversity, sequence-specific secondary structures, biomolecular recognition, high biocompatibility, and ease of synthesis [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. As a minimal-recognition module, the dipeptide Phe-Phe (FF), which can easily assemble into various ordered structures, is the most studied because of its mechanical, electrical and optical properties [ 16 , 17 , 18 , 19 , 20 , 21 ].…”