In PLOS Genetics, a University of Wisconsin at Milwaukee team explores the functional consequences of rare, gain-of-function changes to the voltage-gated calcium channel-coding gene CACNA1C that appear de novo in individuals with a high-penetrance autism spectrum disorder-related condition called Timothy syndrome. Based on their experiments in Caenorhabditis elegans models with or without variants in a CACNA1C homolog, the researchers proposed a model in which the Timothy syndrome-related alterations may upend typical axon targeting and regulation, leading to detectable light response in the worms. "Our results suggest that the Timothy syndrome mutations disrupt axon targeting and behavior by interacting with genes that promote selective autophagy, the process through which cellular components are selected for degradation."
Researchers from the University of Alabama at Birmingham compare strains in the gut microbial communities of dozens of twin adults or twin children who did or did not live in the same household for a paper appearing in PLOS One. Using a single nucleotide variant-based strain identification method, the team searched for shared gut microbial strains in data for two dozen twin children and 50 adult twins, including individuals who had shared a home or lived apart for decades. While twins who shared a home for long stretches followed by short period apart tended to share specific strains, the authors note that "[c]hanges in the host environmental conditions over time can impact the stability landscape of the gut microbial community, resulting in the appearance of new strains that could potentially impact microbe interactions that are essential for function in human health."
A team led by investigators at the Lawrence Livermore National Laboratory and the University of California, Davis, takes a closer look at Zika virus (ZIKV) genomics and epidemic epidemiology, in combination with ZIKV features in mice in the lab, for another PLOS One paper. By bringing together genome sequence information for hundreds of ZIKV isolates collected before and during the 2015 to 2016 epidemic, the researchers tracked down mutations and newly established consensus sequences in the epidemic strains, particularly affecting genes that code for proteins on the surface of the ZIKV. "[T]he use of multiscale modeling for identifying mutations or combinations of mutations that impact epidemic transmission and phenotypic impact can aid of formation of hypotheses which can then be tested using reverse genetics," the authors say.