How does the polymerase of non-segmented negative strand RNA viruses commit to transcription or genome replication?

The , or non-segmented negative-sense RNA viruses (nsNSVs), includes significant human pathogens, such as respiratory syncytial virus, parainfluenza virus, measles virus, Ebola virus, and rabies virus. Although these viruses differ widely in their pathogenic properties, they are united by each having a genome consisting of a single strand of negative-sense RNA. Consistent with their shared genome structure, the nsNSVs have evolved similar ways to transcribe their genome into mRNAs and replicate it to produce new genomes.

Distinctive features of the respiratory syncytial virus priming loop compared to other non-segmented negative strand RNA viruses.

De novo initiation by viral RNA-dependent RNA polymerases often requires a polymerase priming residue, located within a priming loop, to stabilize the initiating NTPs. Polymerase structures from three different non-segmented negative strand RNA virus (nsNSV) families revealed putative priming loops in different conformations, and an aromatic priming residue has been identified in the rhabdovirus polymerase. In a previous study of the respiratory syncytial virus (RSV) polymerase, we found that Tyr1276, the L protein aromatic amino acid residue that most closely aligns with the rhabdovirus priming residue, is not required for RNA synthesis but two nearby residues, Pro1261 and Trp1262, were required.

RSV M2-1 Protein in Complex with RNA: Old Questions Are Answered and a New One Emerges.

The respiratory syncytial virus (RSV) M2-1 protein is essential for virus transcription. In this issue of Structure, Gao et al. (2020) describe the crystal structure of M2-1 in complex with RNA.

Draft Genome Sequences of 10 Bacterial Strains Isolated from Root Nodules of Alnus Trees in New Hampshire.

Here, we report the draft genome sequences obtained for 10 bacterial strains isolated from root nodules of trees. These members of the nodule microbiome were sequenced to determine their potential functional roles in plant health. The selected strains belong to the genera , , , , , and .

Stable Transformation of the Actinobacteria spp.

A stable and efficient plasmid transfer system was developed for nitrogen-fixing symbiotic actinobacteria of the genus , a key first step in developing a genetic system. Four derivatives of the broad-host-range cloning vector pBBR1MCS were successfully introduced into different strains by a filter mating with strain BW29427. Initially, plasmid pHKT1 that expresses green fluorescent protein (GFP) was introduced into strain CcI3 at a frequency of 4.

Simple colony PCR procedure for the filamentous actinobacteria Frankia.

Molecular analysis of the filamentous actinobacteria Frankia is laborious because of the slow growth rate and required biomass needed for these techniques. An efficient and simple colony PCR protocol for Frankia was developed that saved time for analysis of any Frankia strains growing on a plate. Previously, it took 5-6 weeks to get the correct size Frankia colonies on plates and then a minimum of 5 weeks of growth in liquid culture for DNA extraction.