RNA

About: RNA is a research topic. Over the lifetime, 111695 publications have been published within this topic receiving 5475262 citations. The topic is also known as: ribonucleic acid.

Rapid Evolution of RNA Viruses

Abstract: The high error rate inherent in all RNA synthesis provides RNA virus genomes with extremely high mutation rates. Thus nearly all large RNA virus clonal populations are quasispecies collections of differing, related genomes (14, 49). These rapidly mutating populations can remain remarkably stable under certain conditions of replication. Under other conditions, virus-population equilibria become disturbed, and extremely rapid evolution can result. This extreme variability and rapid evolution can cause severe problems with previously unknown virus diseases (such as AIDS). It also presents daunting challenges for the design of effective vaccines for the control of diseases caused by rapidly evolving RNA virus populations.

An RNA motif that binds ATP

Abstract: RNAs that contain specific high-affinity binding sites for small molecule ligands immobilized on a solid support are present at a frequency of roughly one in 10(10)-10(11) in pools of random sequence RNA molecules. Here we describe a new in vitro selection procedure designed to ensure the isolation of RNAs that bind the ligand of interest in solution as well as on a solid support. We have used this method to isolate a remarkably small RNA motif that binds ATP, a substrate in numerous biological reactions and the universal biological high-energy intermediate. The selected ATP-binding RNAs contain a consensus sequence, embedded in a common secondary structure. The binding properties of ATP analogues and modified RNAs show that the binding interaction is characterized by a large number of close contacts between the ATP and RNA, and by a change in the conformation of the RNA.

LGP2 is a positive regulator of RIG-I– and MDA5-mediated antiviral responses

Abstract: RNA virus infection is recognized by retinoic acid-inducible gene (RIG)-I-like receptors (RLRs), RIG-I, and melanoma differentiation-associated gene 5 (MDA5) in the cytoplasm RLRs are comprised of N-terminal caspase-recruitment domains (CARDs) and a DExD/H-box helicase domain The third member of the RLR family, LGP2, lacks any CARDs and was originally identified as a negative regulator of RLR signaling In the present study, we generated mice lacking LGP2 and found that LGP2 was required for RIG-I- and MDA5-mediated antiviral responses In particular, LGP2 was essential for type I IFN production in response to picornaviridae infection Overexpression of the CARDs from RIG-I and MDA5 in Lgp2(-/-) fibroblasts activated the IFN-beta promoter, suggesting that LGP2 acts upstream of RIG-I and MDA5 We further examined the role of the LGP2 helicase domain by generating mice harboring a point mutation of Lys-30 to Ala (Lgp2 (K30A/K30A)) that abrogated the LGP2 ATPase activity Lgp2 (K30A/K30A) dendritic cells showed impaired IFN-beta productions in response to various RNA viruses to extents similar to those of Lgp2(-/-) cells Lgp2(-/-) and Lgp2 (K30A/K30A) mice were highly susceptible to encephalomyocarditis virus infection Nevertheless, LGP2 and its ATPase activity were dispensable for the responses to synthetic RNA ligands for MDA5 and RIG-I Taken together, the present data suggest that LGP2 facilitates viral RNA recognition by RIG-I and MDA5 through its ATPase domain

Oligonucleotide n-alkylphosphoramidates

Abstract: Oligonucleotide N-alkylphosphoramidates useful for combatting diseases by biochemical intervention at the RNA and DNA level are disclosed.