New, Improved Mammalian Tree of Life

Yingying Han, Rune Bruls, Maria Carrillo, Christian Keysers and co-authors show that when one rat witnesses another receive electric shocks, the rats transfer information in both directions. Simulations show that a phenomenon typically associated with empathy and prosociality may actually have evolved to serve the more selfish purpose of danger detection.

Activation of phagocytes rapidly expands the endo-lysosomal system and promotes antigen presentation. Victoria Hipolito, Roberto Botelho and colleagues find that endo-lysosome expansion was driven by mTORC1-dependent enhanced translation, revealing regulated translation as a mechanism to remodel membrane organelles in response to external signals and stresses.

Liver fibrosis is characterized by hepatic damage, an inflammatory response, and hepatic stellate cell activation, but the underlying mechanisms remain unclear. Zhichao Wang, Dan Cao, Gang Wang and co-workers reveal that the transcriptional Mediator subunit MED23 regulates the pathogenesis of liver fibrosis by controlling the production of inflammatory cytokines such as CCL5 and CXCL10.