An international team led by investigators at Emory University explore human host B cell responses over time in Ebola virus (EBOV) infection survivors. Using ELISA and viral plaque reduction assays, the researchers profiled antibodies developed against an EBOV surface glycoprotein in blood samples from four Ebola individuals who survived a West African outbreak that started in 2014. There, they found that EBOV infection initially led to pronounced naïve B cell recruitment, followed by neutralizing or non-neutralizing protective antibody formation. Some protective antibodies seemed to converge across multiple individuals, the authors note, while three years of post-infection follow up revealed new combinations and permutations for antibodies developed against the virus, even months after the acute infection stage subsided.
A team from the UK identifies two proteins that seem to suppress cellular events leading to premature messenger RNA termination. Using CRISPR gene editing, the researchers established human cell lines missing one or both copies of the proposed anti-terminator proteins, SCAF4 and SCAF8. Together with RNA sequencing, transcriptional readthrough assays, fluorescence tagging, immunoprecipitation, cell growth profiling and other approaches, the editing experiments made it possible to tease out interactions and functions for SCAF4 and SCAF8. Overall, the authors conclude, the mRNA anti-terminator proteins "coordinate the transition between elongation and termination, ensuring correct [polyadenylation] site selection and [RNA polymerase II] transcriptional termination in human cells."
Finally, researchers from the University of Toulouse, the University of Copenhagen, and elsewhere describe two previously unappreciated ancient, extinct horse lineages from Iberia and Siberia. The team identified the lineages through a largescale analysis of domestic horse evolution, which included genome sequences for 129 ancient horses. The analysis also highlighted ancestral horses that provided the most pronounced ancestry to modern domestic horses at different points in their history, while identifying a decline in genetic diversity in relatively recent horse history, which appeared to reflect modern breeding preferences. GenomeWeb has more on the study, here.