New factors and signaling pathways for developmental regulation

The developmental process is a highly complicated process for building multicellular organisms. JMCB haspublished several researchworks inrecentcollections on this topic (Wu, 2013, 2014). In the present issue, five more articles report new biological factors and cell signaling pathways that are discovered controlling the developmental process. These findings might provide new insights into the intricate developmental regulation. Dr Wu’s group and collaborators reported in this issue that a microRNA, miR-181, is essential for the onset of embryo implantation. The authors showed that the upregulation of exogenous miR-181 expression resulted in impaired embryo implantation of mice. They further showed that Emx2-mediated miR-181 expression could directly downregulate the expression of leukemia inhibitory factor (LIF), which