Using a combination of transcriptomic, imaging, and genetic lineage labeling methods, a University of Oxford team has mapped the origin of the embryonic mouse heart at single-cell resolution. As reported in this week's Science, the scientists micro-dissected a portion of the embryonic mouse heart to collect cells involved in the formation of the cardiac crescent that subsequently transform into the linear heart tube. Using RNA sequencing, high-resolution imaging, and time-lapse microscopy, they were able to track the development of progenitor heart cell populations over a 12-hour period, providing "detailed insights into the formation of early cardiac cell types, with particular relevance to the development of cell-based cardiac regenerative therapies."
Through an analysis of genome-wide data from the remains of dozens of individuals who lived in northeast Asia between the Late Upper Paleolithic to the Medieval era, a team led by scientists from Stockholm University have generated insights into gene flow and admixture events that reveal the complex population history of the region. The researchers produced whole-genome sequencing data for 40 people who lived 16,900 to 550 years ago, representing the Russian regions of Yakutia, Trans-Baikal, Cis-Baikal, Krasnoyarsk Krai, and Amur Oblast. They find that while populations east of Lake Baikal remained relatively stable from the Mesolithic to the Bronze Age, those from Yakutia and west of Lake Baikal witnessed major population transformations from the Late Upper Paleolithic to the Neolithic, as well as during the Bronze Age, respectively. They also uncover evidence of the most northeastern ancient occurrence of the plague-related bacterium, Yersinia pestis. The findings, which appear in Science Advances, "indicate the highly connected and dynamic nature of northeast Asia populations throughout the Holocene," the study's authors write.