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There is an unmet need for carriers that can deliver nucleic acids (NAs) to cancer cells and tumors to perpetuate gene regulation and manage disease progression. Membrane-wrapped nanoparticles (NPs) can be loaded with exogenously designed nucleic acid cargoes, such as plasmid deoxyribonucleic acid (pDNA), messenger ribonucleic acid (mRNA), small interfering RNA (siRNA), microRNA (miRNA), and immunostimulatory CpG oligodeoxynucleotides (CpG ODNs), to mitigate challenges presented by NAs’ undesirable negative charge, hydrophilicity, and relatively large size. By conjugating or encapsulating NAs within membrane-wrapped NPs, various physiological barriers can be overcome so that NAs experience increased blood circulation half-lives and enhanced accumulation in intended sites. This review discusses the status of membrane-wrapped NPs as NA delivery vehicles and their advancement in gene regulation for cancer management in vitro and in vivo . With continued development, membrane-wrapped NPs have great potential as future clinical tools to treat cancer and other diseases with a known genetic basis.
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A liquid crystal world for the origins of life
Nucleic acids (NAs) in modern biology accomplish a variety of tasks, and the emergence of primitive nucleic acids is broadly recognized as a crucial step for the emergence of life. While modern NAs have been optimized by evolution to accomplish various biological functions, such as catalysis or transmission of genetic information, primitive NAs could have emerged and been selected based on more rudimental chemical–physical properties, such as their propensity to self-assemble into supramolecular structures. One such supramolecular structure available to primitive NAs are liquid crystal (LC) phases, which are the outcome of the collective behavior of short DNA or RNA oligomers or monomers that self-assemble into linear aggregates by combinations of pairing and stacking. Formation of NA LCs could have provided many essential advantages for a primitive evolving system, including the selection of potential genetic polymers based on structure, protection by compartmentalization, elongation, and recombination by enhanced abiotic ligation. Here, we review recent studies on NA LC assembly, structure, and functions with potential prebiotic relevance. Finally, we discuss environmental or geological conditions on early Earth that could have promoted (or inhibited) primitive NA LC formation and highlight future investigation axes essential to further understanding of how LCs could have contributed to the emergence of life.
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- Award ID(s):
- 2005212
- PAR ID:
- 10496613
- Editor(s):
- NA
- Publisher / Repository:
- Portland Press
- Date Published:
- Journal Name:
- Emerging Topics in Life Sciences
- Edition / Version:
- NA
- Volume:
- 6
- Issue:
- 6
- ISSN:
- 2397-8554
- Page Range / eLocation ID:
- 557 to 569
- Subject(s) / Keyword(s):
- DNA, nucleic acid, liquid crystal, autocatalysis
- Format(s):
- Medium: X Other: NA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1042/ETLS20220081
