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We describe herein topological mRNA capture using branched oligodeoxynucleotides (ODNs) with multiple reactive functional groups. These fragmented ODNs efficiently formed topological complexes on template mRNA in vitro. In cell-based experiments targeting AcGFP mRNA, the bifurcated reactive ODNs showed a much larger gene silencing effect than the corresponding natural antisense ODN. [ABSTRACT FROM AUTHOR]

Starting with the clinical application of two vaccines in 2020, mRNA therapeutics are currently being investigated for a variety of applications. Removing immunogenic uncapped mRNA from transcribed mRNA is critical in mRNA research and clinical applications. Commonly used capping methods provide maximum capping efficiency of around 80–90% for widely used Cap-0- and Cap-1-type mRNAs. However, uncapped and capped mRNA possesses almost identical physicochemical properties, posing challenges to their physical separation. In this work, we develop hydrophobic photocaged tag-modified cap analogs, which separate capped mRNA from uncapped mRNA by reversed-phase high-performance liquid chromatography. Subsequent photo-irradiation recovers footprint-free native capped mRNA. This approach provides 100% capping efficiency even in Cap-2-type mRNA with versatility applicable to 650 nt and 4,247 nt mRNA. We find that the Cap-2-type mRNA shows up to 3- to 4-fold higher translation activity in cultured cells and animals than the Cap-1-type mRNA prepared by the standard capping method. Removing immunogenic uncapped mRNA from transcribed mRNA can be challenging, but is critical in mRNA research and clinical applications such as vaccines. Here, authors develop hydrophobic photocaged tag-modified cap analogs, which can be used to separate capped mRNA from uncapped mRNA, with subsequent tag removal using photo-irradiation. [ABSTRACT FROM AUTHOR]

Here we report the development of an equimolar conjugate of a metal – organic cage (MOC) and DNA (MOC-DNA). Several MOC-DNA conjugates were assembled into a programmed structure by coordinating with a template DNA having a complementary base sequence. Moreover, conjugation with the MOC drastically enhanced the permeability of DNA through the lipid bilayer, presenting great potential as a drug delivery system. [ABSTRACT FROM AUTHOR]

Cell migration plays an important role in multicellular organism development. The cellular slime mold Dictyostelium discoideum is a useful model organism for the study of cell migration during development. Although cellular ATP levels are known to determine cell fate during development, the underlying mechanism remains unclear. Here, we report that ATP‐rich cells efficiently move to the central tip region of the mound against rotational movement during the mound phase. A simulation analysis based on an agent‐based model reproduces the movement of ATP‐rich cells observed in the experiments. These findings indicate that ATP‐rich cells have the ability to move against the bulk flow of cells, suggesting a mechanism by which high ATP levels determine the cell fate of differentiation. [ABSTRACT FROM AUTHOR]

Multicellular organisms contain various differentiated cells. Fate determination of these cells remains a fundamental issue. The cellular slime mold Dictyostelium discoideum is a useful model organism for studying differentiation; it proliferates as single cells in nutrient‐rich conditions, which aggregate into a multicellular body upon starvation, subsequently differentiating into stalk cells or spores. The fates of these cells can be predicted in the vegetative phase: Cells expressing higher and lower levels of omt12 differentiate into stalk cells and spores, respectively. However, omt12 is merely a marker gene and changes in its expression do not influence the cell fate, and determinant factors remain unknown. In this study, we analyzed cell fate determinants in the stalk‐destined and spore‐destined cells that were sorted based on omt12 expression. Luciferase assay demonstrated higher levels of intracellular ATP in the stalk‐destined cells than in the spore‐destined cells. Live‐cell observation during development using ATP sensor probes revealed that cells with higher ATP levels differentiated into stalk cells. Furthermore, reducing the ATP level by treating with an inhibitor of ATP production changed the differentiation fates of the stalk‐destined cells to spores. These results suggest that intracellular ATP levels influence cell fates in D. discoideum differentiation. [ABSTRACT FROM AUTHOR]