In the early, online edition of the Proceedings of the National Academy of Sciences, an international team led by investigators at the University of California, Irvine, describes efforts to sequence and analyze the genome and transcriptome of the Asian tiger mosquito, Aedes albopictus. After putting together an almost 1,970 million base genome sequence for a Foshan strain of Ae. albopictus, the researchers identified 17,539 predicted protein-coding genes in the mosquito species, which has been implicated in the spread of dengue fever, Chikungunya fever, and other diseases. Along with repeat sequences and sequences that seem to be nabbed from flaviviruses, they note, the mosquito's genome appears to be rife with expansions involving gene families contributing to immunity, scent detection, insecticide resistance, and more.
With the help of genome, microRNA, transcriptome, and methylome profiling on ant and wasp brain tissues, researchers from University of Bristol, the Babraham Institute, and elsewhere explore the molecular features associated with eusocial insect lifestyles. The team focused on the aculeate wasp, Polistes canadensis, and the Dinoponera quadriceps ant, insects from simple eusocial societies marked by the ability of members to switch between different phenotypes, even after adulthood. Results of the analysis uncovered somewhat understated transcriptional differences between ant and wasp individuals with different phenotypes — gene expression changes that did not seem to stem from phenotype-related methylation or miRNA shifts.
Finally, a McGill University-led team takes a look at bacterial diversity and virulence features in Mycobacterium tuberculosis isolates collected in Inuit populations from Nunavik, Quebec over more than two decades. The researchers sequenced 163 M. tuberculosis clinical isolates collected from 11 villages in the Nunavik region, comparing the sequences to one another and to representatives from seven main M. tuberculosis lineages. Their results point to a lone TB introduction of M. tuberculosis from the Euro-American TB lineage 4 in the area in around 1919 or 1920. Since then, the isolates seem to have experienced only weak selection, the study's authors say, and have not acquired genomic features linked to enhanced virulence. GenomeWeb has more on the study, here.