In PLOS Genetics, researchers from Israel explore ties between mitochondrial variation and gene expression using RNA sequence data for hundreds of lymphoblast cell lines developed from 1000 Genomes Project samples. From sequences in 454 of the cell lines, the team uncovered distinct mitochondrial gene expression in samples from individuals in mitochondrial haplogroup L, the most commonly described African haplogroup. The expression differences appeared to coincide with the expression of RNA binding genes in the nuclear genome, the study authors explain, hinting at "an ancient regulatory transition of mtDNA-encoded genes as humans left Africa to populate the rest of the world."
The two color forms of Aedes aegypti mosquitos appear to be genetically indistinguishable, according to a study in PLOS Neglected Tropical Diseases. A team from Australia and Singapore used double-digest RAD sequencing to assess mitochondrial sequences and nearly 16,600 nuclear SNPs in 45 Ae. aegypti mosquitoes from Australia and 29 Ae. aegypti mosquitoes from Singapore. Although they detected two-dozen mitochondrial haplotypes, some differing by mosquito color, the researchers found that the pale queenslandensis and the darker type forms could not be distinguished genomically, but instead clustered by geography.
Finally, Swiss and German researchers report on genomic and transcriptomic patterns in a so-called BTEX-degrading Pseudomonas veronii that is capable of breaking down aromatic hydrocarbons such as benzene and toluene for a paper appearing in PLOS One. The team did genome sequencing on P. veronii 1YdBTEX2, analyzing the resulting 8 million base genome alongside RNA sequencing data in P. veronii 1YdBTEX2 exposed toluene in soil or liquid culture for an hour. The work "provides valuable insights into the cellular functions involved in the early adaptation response to organic solvents in sandy soil," the authors note.