In PLOS Genetics, researchers from France and Spain scour butterfly and moth genomes in search of sequences stemming from parasitoid wasps and the symbiotic bracoviruses they use to take over caterpillars as they reproduce. Based on sequences for host and non-host butterfly and moth genomes, the team uncovered bracovirus — and in some cases, braconid wasp — genes in the monarch butterfly, beet armyworm, fall armyworm, and other lepidopteran species that aren't typically used by braconid wasps to reproduce, pointing to potential horizontal gene transfer events due by wasps inadvertently stinging non-host species. GenomeWeb has more on the study, here.
A team from Brazil characterizes the nuclear sub-proteome of the Chagas disease-causing parasite Trypanosoma cruzi for a paper appearing in PLOS One. After purifying the nuclear portions of T. cruzi cells with the help of a sucrose density gradient and centrifugation, the researchers combined tandem mass spectrometry with liquid chromatography to spell out the protein content of the nuclear compartment. Their search uncovered 864 proteins, including 272 previously undescribed candidate proteins and hundreds of proteins not found in T. cruzi proteomes assessed in the past.
A PLOS Biology study highlights a particularly high mutation rate in HIV-1 viruses occurring in vivo. Spanish researchers attempted to track spontaneous HIV-1 mutation rates by sequencing and comparing samples from peripheral blood mononuclear cells and plasma-derived samples from the same patients. Their results suggest that far more premature stop codon mutations turn up in the blood mononuclear cells, suggesting many mutations are lethal to the virus. Moreover, rampant mutation was less common in individuals whose HIV-1 infections progressed particularly quickly. "Our work highlights the fine balance for HIV-1 between enough mutation to evade host responses and too much mutation that can inactivate the virus," they write.