In Science Advances, a team of US and European scientists presents a new high-quality genome assembly of the donkey. Using Chicago HiRise assembly technology, the investigators achieved subchromosomal scaffolds they say are four times larger than previously published donkey assemblies. These scaffolds enabled comparisons between the genomes of horses and donkeys — which share a common ancestor dating back to about 4 million years ago — to examine chromosomal rearrangements that that likely played an active role in the animals divergence and, ultimately, speciation.
Over in Science this week, two independent research groups publish studies visualizing herpes simplex virus types 1 and 2 capsids, offering insights into the viruses and possible ways to disrupt their life cycles to combat infection. Using cryo-electron microscopy, the first team determined the structure of HSV-1 capsids to around 3.5 angstroms, while the second team imaged HSV-2 capsids at 3.1 angstroms — far greater resolutions than previous imaging efforts. Each of the studies provide a detailed look at viral capsid architecture including intermolecular bonds and protein-protein interactions, and show that HSV capsid proteins have extensive conformational diversity.
Also in Science Advances, a group of German and Swedish investigators publish a study examining the genomes of six baleen whale species in order to better understand the evolution of what are the largest animals living on Earth. They sequenced the genomes of the blue whale and five other baleen whales, and built a baleen species tree that could be examined for phylogenetic conflicts. They conclude that the formation of new baleen species occurred under introgressive gene flow. "Especially in marine environments, sympatric speciation might be common and raise the question how genetic divergence can be established," the authors write. The Scan has more on this, here.