In the early, online edition of the Proceedings of the National Academy of Sciences, researchers from France and Korea explore innate immune interactions with the tuberculosis pathogen Mycobacterium tuberculosis. The team turned to transposon mutagenesis to systematically alter a virulent strain of M. tuberculosis, tracking the consequences of these mutations in an infected human cell line carrying a reporter construct that picked up innate immune activity in the host cells. The search led to mutated pathogens that prompted enhanced immunity in the host, leading to M. tuberculosis glycolipids that seem to help staunch such immunity in wild-type pathogens.
A team from Japan and Belgium identifies a role for a cytoplasmic microtubule organizing center (MTOC)-like structure in plants with asymmetric cell division. With live imaging of asymmetric cell division in cell types from gametophore tissue in Physcomitrella patens moss — a centrosome-free plant that relies on a preprophase band microtubule structure during mitotic cell division — the researchers tracked down new microtubule organizing structures in the cell cytoplasm that transiently form during prophase and contribute to spindle orientation in metaphase. These so-called gametosomes resembled mitochondrial polar caps described in other plant types, prompting follow up experiments in tobacco tissue culture cells.
Finally, members of a University of Iowa-led team demonstrate the feasibility of using CRISPR/Cas9 gene editing to interfere with glaucoma-causing, gain-of-function forms of the MYC gene in a mouse model of primary open-angle glaucoma and in human trabecular meshwork eye cell cultures. After taking a crack at the gene editing approach in cell lines with or without an early-onset primary open-angle glaucoma-associated mutation in MYOC, the researchers used adenovirus to deliver the CRISPR construct in young and adult mouse models of the disease. GenomeWeb has more on the study.