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Cells often spatially organize biomolecules to regulate biological interactions. Synthetic mimicry of complex spatial organization may provide a route to similar levels of control for artificial systems. As a proof-of-principle, we constructed an RNA-extruding nanofactory using a DNA-origami barrel with an outer diameter of 60 nm as a chassis for integrated rolling-circle transcription and processing of RNA through spatial organization of DNA templates, RNA polymerases, and RNA endonucleases. The incorporation efficiency of molecular components was quantified to be roughly 50% on designed sites within the DNA-origami chassis. Each integrated nanofactory with RNA-producing units, composed of DNA templates and RNA polymerases, produced 100 copies of target RNA in 30 min on average. Further integration of RNA endonucleases that cleave rolling-circle transcripts from concatemers into monomers resulted in 30% processing efficiency. Disabling spatial organization of molecular components on DNA origami resulted in suppression of RNA production as well as processing.

There is increasing demand for single-stranded DNA (ssDNA) of lengths >200 nucleotides (nt) in synthetic biology, biological imaging and bionanotechnology. Existing methods to produce high-purity long ssDNA face limitations in scalability, complexity of protocol steps and/or yield. We present a rapid, high-yielding and user-friendly method for in vitro production of high-purity ssDNA with lengths up to at least seven kilobases. Polymerase chain reaction (PCR) with a forward primer bearing a methanol-responsive polymer generates a tagged amplicon that enables selective precipitation of the modified strand under denaturing conditions. We demonstrate that ssDNA is recoverable in ∼40–50 min (time after PCR) with >70% yield with respect to the input PCR amplicon, or up to 70 pmol per 100 μl PCR reaction. We demonstrate that the recovered ssDNA can be used for CRISPR/Cas9 homology directed repair in human cells, DNA-origami folding and fluorescent in-situ hybridization.

We present a rapid, scalable, user-friendly method for in vitro production of high-purity single-stranded DNA (ssDNA) ranging from 89–3315 nucleotides in length. PCR with a forward primer bearing a methanol-responsive polymer generates a tagged amplicon that enables selective precipitation of the modified strand under denaturing conditions. We demonstrate that the recovered ssDNA can be used for CRISPR/Cas9 homology-directed repair in human cells, DNA-origami folding, and fluorescent in situ hybridization.

La presente investigación tuvo como objetivo establecer los factores determinantes que incidieron en el comportamiento de las exportaciones agrícolas primarias y derivadas del Perú hacia los Estados Unidos, en el periodo 2000-2017, teniendo como base la teoría de la demanda marshalliana aplicada al comercio internacional. Se partió construyendo una nueva clasificación de exportaciones agrícolas de acuerdo a su nivel de transformación o valor agregado, a fin de buscar una alternativa a la actual clasificación que clasifica a las exportaciones en tradicionales y no tradicionales. Para ello, se estimaron tres modelos dinámicos de agroexportaciones del Perú a los Estados Unidos y se realizaron pronósticos para los próximos 16 trimestres. Además, se analizó las exportaciones agroindustriales del Perú a los Estados Unidos de acuerdo a la clasificación de exportaciones propuesta. Los resultados del modelo revelan que las variables proxy: Gasto de Consumo Personal (Personal Consumption Expenditure-PCE) de los Estados Unidos, el Tipo de Cambio Real Bilateral; y el componente autorregresivo influyen en la demanda de las agroexportaciones peruanas (sector industrial, primarias y derivadas) a los Estados Unidos, en el periodo evaluado. The present investigation aims to establish the determining factors that influenced the behavior of primary and derived agricultural exports from Peru to the United States, in the period 2000-2017, based on the theory of Marshallian demand, applied to international trade. It started by building a new classification of agricultural exports according to its level of transformation or added value, in order to find an alternative to the current classification that classifies exports into traditional and non-traditional. For this, three dynamic models of agro-exports from Peru to the United States were estimated and forecasts were made for the next 16 quarters. In addition, the agro-industrial exports from Peru to the United States were analyzed according to the proposed export classification. The results of the model reveal that the proxy variables: Personal Consumption Expenditure-PCE of the United States, the Bilateral Real Exchange Rate; and the autoregressive component influences the demand of Peruvian agro-exports (industrial, primary and derived sectors) to the United States, in the period evaluated. Tesis