In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

Q: The cellular role of DNA is relatively limited, perhaps because of the restrictions imposed by bonding between complementary strands. Outside the cell, however, nanoengineers are uncovering the many hidden talents of DNA. The DNA sequence is able to process information in biochemical assays, its structure is an ideal building material, and its folding pathway allows DNA to move and respond to its environment. Here, I review several innovative applications of designed DNA molecules, some underlying design principles and the prospects for future developments. The applications of new DNA-based technologies range from molecular diagnostics to protein purification and from therapeutics to the assembly of tiny electronic circuits. These uses exploit the properties of DNA at three levels -sequence only, structure (which depends on sequence) and folding pathways (which depend on both sequence and structure) -as the following examples show. By taking their cue from the genetic code found in nature, nanoengineers are now using DNA sequences in vitro to direct the synthesis and evolution of molecules with new functions and reactive properties. When attached to other molecules, detection methods that exploit DNA sequences allow complementary molecules to be identified at extremely low concentrations. DNA sequences can also be used, in a non-biological setting, to control the layout of electronic components in a nanocircuit. DNA strands can fold into stable structures that have valuable functional and material properties. Sensitive methods for detecting DNA have been extended to detect proteins and other macromolecular targets of DNA aptamers -that is, nucleic-acid molecules that have high binding specificity for their targets. Lattices and even three-dimensional (3D) objects have been self-assembled from rigid DNA structures. DNA lattices can organize proteins and nanoelectronic components on a surface with unprecedented precision, making it possible to gain a better understanding of the properties and interactions of proteins. The folding pathway of a DNA molecule to its stable structure allows it to move and perform mechanical functions. The energy released in DNA-folding pathways has been used in vitro to drive motors, providing the ability to release, grab or cleave target molecules and even to control the release of drugs, depending on the outcome of certain diagnostic tests. This review focuses on the recent developments in generating rationally designed DNA molecules and their applications. The past decade has seen huge advances in the development of design principles, particularly by exploiting DNA structure and folding pathways, but also in applications of designed DNA sequences. Together, techniques for the in vitro selection or molecular evolution of DNA molecules from random pools have given spectacular yields, including DNA aptamers and enzymes, which can inhibit the expression of harmful genes or disrupt protein function. Excellent reviews of selected DNA molecules can be found elsewhere 1-3 ; this paper includes only examples of designed DNA molecules, or molecules that combine both selected and designed Abstract | Long admired for its informational role in the cell, DNA is now emerging as an ideal molecule for molecular nanotechnology. Biologists and biochemists have discovered DNA sequences and structures with new functional properties, which are able to prevent the expression of harmful genes or detect macromolecules at low concentrations. Physical and computational scientists can design rigid DNA structures that serve as scaffolds for the organization of matter at the molecular scale, and can build simple DNA-computing devices, diagnostic machines and DNA motors. The integration of biological and engineering advances offers great potential for therapeutic and diagnostic applications, and for nanoscale electronic engineering.

A: Designed DNA molecules: principles and applications of molecular nanotechnology
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Q: Structured RNA elements may control virus replication, transcription and translation, and their distinct features are being exploited by novel antiviral strategies. Viral RNA elements continue to be discovered using combinations of experimental and computational analyses. However, the wealth of sequence data, notably from deep viral RNA sequencing, viromes, and metagenomes, necessitates computational approaches being used as an essential discovery tool. In this review, we describe practical approaches being used to discover functional RNA elements in viral genomes. In addition to success stories in new and emerging viruses, these approaches have revealed some surprising new features of well-studied viruses e.g., human immunodeficiency virus, hepatitis C virus, influenza, and dengue viruses. Some notable discoveries were facilitated by new comparative analyses of diverse viral genome alignments. Importantly, comparative approaches for finding RNA elements embedded in coding and non-coding regions differ. With the exponential growth of computer power we have progressed from stem-loop prediction on single sequences to cutting edge 3D prediction, and from command line to user friendly web interfaces. Despite these advances, many powerful, user friendly prediction tools and resources are underutilized by the virology community.

A: Know Your Enemy: Successful Bioinformatic Approaches to Predict Functional RNA Structures in Viral RNAs
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Q: The cellular receptor for human coronavirus NL63 (HCoV-NL63), a group I coronavirus, is angiotensin-converting enzyme2 (ACE2). ACE2 is also the receptor for the SARS coronavirus (SARS-CoV), a group II coronavirus. Here we describe the ability of HCoV-NL63 to utilize a number of ACE2 variants previously characterized as SARS-CoV receptors. Several ACE2 variants that reduced SARS-CoV S-protein association similarly reduced that of HCoV-NL63, whereas alteration of a number of solvent-exposed ACE2 residues did not interfere with binding by either S protein. One notable exception is ACE2 residue 354, at the boundary of the SARS-CoV binding site, whose alteration markedly inhibited utilization by the HCoV-NL63 but not SARS-CoV S proteins. In addition, the SARS-CoV S-protein receptor-binding domain inhibited entry mediated by the HCoV-NL63 S protein. These studies indicate that HCoV-NL63, like SARS-CoV, associates region of human ACE2 that includes a key loop formed by β-strands 4 and 5.

A:
The S proteins of human coronavirus NL63 and severe acute respiratory syndrome coronavirus bind overlapping regions of ACE2
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