Editor's Note: Some of the articles described below are not yet available at the PNAS site, but they are scheduled to be posted some time this week.
In the early, online edition of the Proceedings of the National Academy of Sciences, Max Planck Institute for Infection Biology researcher Kai Matuschewski and colleagues from Germany and the US describe the high genetic diversity detected amongst malaria parasites infecting West African bats. Using microscopic methods, diagnostic PCR, and sequencing to test blood samples from hundreds of bats caught in three remote regions of an Upper Guinean forest, the team detected parasite species from four genera. Among them were Plasmodium species resembling those found in rodents, the study authors note, though the malaria parasites from other genera included genetically diverse representatives from a genus called Hepatocystis as well as phylogenetically distinct species from the Nycteria genus.
By sequencing transcripts from immune cells tasked with secreting antibodies and applying a bioinformatics-based analysis, a team from the National Human Genome Research Institute and Columbia University uncovered new representatives from a recently described class of antibodies capable of neutralizing HIV-1 — work they outline in another PNAS paper. The so-called VRC01 antibodies were found in B-cell samples from one donor individual. Through phylogenetic analysis and comparisons of antibodies from that individual and other donors, the study's authors defined heavy- and light-chain VRC01 sequences. "This 'cross-donor analysis' yielded heavy chains with little sequence homology to previously identified VRC01 class heavy chains," they write. "Nonetheless, when reconstituted with the light chain from VRC01, half of the heavy chain chimeric antibodies showed substantial neutralization potency and breadth."
Nearly two-thirds of newly duplicated genes in the Drosophila genome are retained as a result of processes that confer fresh functions to the young genes, according to a study by two University of California, Berkeley researchers. The pair used a phylogenetics-based scheme for using gene expression information in related species to explore factors influencing duplicate gene retention. Results of the analysis indicate that neofunctionalization is common in duplicated Drosophila genes. New gene functions typically turning up in younger versions of genes, study authors say, which usually start out being expressed in the testes before taking on roles in other tissues.