Dictated Emergence of Nucleic Acid-Based Constitutional Dynamic Networks by DNA Replication Machineries

Author(s):  
Zhixin Zhou ◽  
Jianbang Wang ◽  
Itamar Willner
2021 ◽  
Vol 12 (15) ◽  
pp. 5473-5483
Author(s):  
Zhixin Zhou ◽  
Jianbang Wang ◽  
R. D. Levine ◽  
Francoise Remacle ◽  
Itamar Willner

A nucleic acid-based constitutional dynamic network (CDN) provides a single functional computational module for diverse input-guided logic operations and computing circuits.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Chen Wang ◽  
Michael P. O’Hagan ◽  
Ehud Neumann ◽  
Rachel Nechushtai ◽  
Itamar Willner

AbstractNucleic acid-based constitutional dynamic networks (CDNs) have recently emerged as versatile tools to control a variety of catalytic processes. A key challenge in the application of these systems is achieving intercommunication between different CDNs to mimic the complex interlinked networks found in cellular biology. In particular, the possibility to interface photochemical ‘energy-harvesting’ processes with dark-operating ‘metabolic’ processes, in a similar way to plants, represents an up to now unexplored yet enticing research direction. The present study introduces two CDNs that allow the intercommunication of photocatalytic and dark-operating catalytic functions mediated by environmental components that facilitate the dynamic coupling of the networks. The dynamic feedback-driven intercommunication of the networks is accomplished via information transfer between the two CDNs effected by hairpin fuel strands in the environment of the system, leading to the coupling of the photochemical and dark-operating modules.


1971 ◽  
Vol 103 (8) ◽  
pp. 1063-1078 ◽  
Author(s):  
Petr Masner ◽  
Vladimir Landa

AbstractOvaries are one of the target organs hit by the nucleic acid antimetabolite 6-azauridine. All the malformations observed are caused by the suppression of mitotic activity, which appears to be the most sensitive to the applied drug. The inhibition of mitosis in the apical trophocytes results in depletion of the nutritive tissue in older females, followed by a disturbance of previtellogenesis and activation of oocytes. The blocked mitotic multiplication of prefollicular tissue results in exhaustion of this layer followed by a disturbance of regular egg chamber formation. The inadequate separation of oocytes by follicular cells causes the arrangement of the oocytes in paired chambers, often blocking the ovariole, or the formation of compound chambers. The oocytes sharing the compound chamber either remain separated by the ooplasmalemma or merge. Eggs with adherent dwarf oocytes or giant fused double eggs are oviposited. Endomitotic DNA replication and amitotic karyokinesis of the follicular cells are not interfered with by 6-azauridine, probably owing to the nucleic acid pools contained in the haemolymph. The lecytholitic cells resorb the ooplasm utilizing the nucleic acid-rich material.


1995 ◽  
Vol 17 (1-2) ◽  
pp. 73-82 ◽  
Author(s):  
M. Salas ◽  
R. Freire ◽  
M.S. Soengas ◽  
J.A. Esteban ◽  
J. Méndez ◽  
...  

2021 ◽  
Author(s):  
Itamar Willner ◽  
Chen Wang ◽  
Ehud Neumann ◽  
Rachel Nechushtai

Abstract Integration of a photosynthetic network with an assimilation, metabolic network is the fundamental prerequisite to construct an “artificial leaf”. Nucleic acid-based constitutional dynamic networks provide the building modules to construct integrated, intercommunicated networks mimicking photosynthesis. Two constitutional dynamic networks composed each of four constituents provide the photosynthetic and metabolic networks. In the photosynthetic network, photoinduced electron transfer from the Zn(II)-protoporphyrin photosensitizer to a bipyridinium electron acceptor is activated, followed by the biocatalytic reduction of NADP+ to NADPH, in analogy to photosystem I in native photosynthesis. In the metabolic network, the biocatalyzed-oxidation of lactate to pyruvate proceeds, followed by the metabolic transformation of pyruvate to L-alanine. The guided dynamic feedback-driven intercommunication of the networks is accomplished, leading to the function as an “artificial leaf”.


2019 ◽  
Vol 20 (13) ◽  
pp. 3173 ◽  
Author(s):  
Hans-Juergen Schulten ◽  
Sherin Bakhashab

Several studies have demonstrated that metformin (MTF) acts with variable efficiency as an anticancer agent. The pleiotropic anticancer effects of MTF on cancer cells have not been fully explored yet. By interrogating the Gene Expression Omnibus (GEO) for microarray expression data, we identified eight eligible submissions, representing five different studies, that employed various conditions including different cell lines, MTF concentrations, treatment durations, and cellular components. A compilation of the data sets of 13 different conditions contained 443 repeatedly up- and 387 repeatedly down-regulated genes; the majority of these 830 differentially expressed genes (DEGs) were associated with higher MTF concentrations and longer MTF treatment. The most frequently upregulated genes include DNA damage inducible transcript 4 (DDIT4), chromodomain helicase DNA binding protein 2 (CHD2), endoplasmic reticulum to nucleus signaling 1 (ERN1), and growth differentiation factor 15 (GDF15). The most commonly downregulated genes include arrestin domain containing 4 (ARRDC4), and thioredoxin interacting protein (TXNIP). The most significantly (p-value < 0.05, Fisher’s exact test) overrepresented protein class was entitled, nucleic acid binding. Cholesterol biosynthesis and other metabolic pathways were specifically affected by downregulated pathway molecules. In addition, cell cycle pathways were significantly related to the data set. Generated networks were significantly related to, e.g., carbohydrate and lipid metabolism, cancer, cell cycle, and DNA replication, recombination, and repair. A second compilation comprised genes that were at least under one condition up- and in at least another condition down-regulated. Herein, the most frequently deregulated genes include nuclear paraspeckle assembly transcript 1 (NEAT1) and insulin induced gene 1 (INSIG1). The most significantly overrepresented protein classes in this compilation were entitled, nucleic acid binding, ubiquitin-protein ligase, and mRNA processing factor. In conclusion, this study provides a comprehensive list of deregulated genes and biofunctions related to in vitro MTF application and individual responses to different conditions. Biofunctions affected by MTF include, e.g., cholesterol synthesis and other metabolic pathways, cell cycle, and DNA replication, recombination, and repair. These findings can assist in defining the conditions in which MTF exerts additive or synergistic effects in cancer treatment.


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