In PLOS Genetics, researchers from China and the US describe a variant in the MAP kinase family gene MKK7 that appears to help in predicting lung cancer risk and patient outcomes in individuals from the Chinese population. The team investigated potential lung cancer associations for a handful of rare variants identified in a retrospective study of more than 5,000 Chinese individuals with the disease and nearly 5,200 without. The search uncovered a rare variant in MKK7 that was linked to higher-than-usual lung cancer risk and more aggressive cases with poorer outcomes. In their follow-up experiments, the investigators found that boosting the expression of the mutation-containing version of MKK7 seemed to enhance xenograft tumor growth and metastasis in mice.
Components in the host's actin-remodeling pathway appear to mediate infection by pathogenic alphaviruses such as Chikungunya or the Venezuelan equine encephalitis virus, according to a study in PLOS Pathogens. A team from the US Army Medical Research Institute of Infectious Diseases and the National Institute of Allergy and Infectious Diseases used a small interfering RNA screen targeting more than 100 trafficking genes to search for molecules that help make it possible for alphaviruses to establish themselves in the HeLa human cell line. The researchers found that alphavirus infection rates dipped when actin-remodeling proteins such as Rac1 or Arp3 were inhibited, pointing to a potential role for actin remodeling in transport of the alphavirus envelope protein to the surface of infected cells.
In a paper appearing in PLOS One, researchers from Malaysia and the UK present findings from a genome sequencing study of Mycobacterium brisbanense, an occasional respiratory tract infection-causing species found in soil, dust, and water samples. The team focused on an isolate obtained from an infected 70-year-old Malaysian individual, using shotgun short read sequences to put together an almost 7.7 million base genome assembly containing an estimated 7,500 protein-coding genes. By comparing the particularly large genome with sequences from almost 150 other Mycobacterium strains in more than two-dozen species, the investigators uncovered genes specific to the strain as well as pathways of potential interest, including urea synthesis genes.