https://www.selleckchem.com/products/acbi1.html Bones do not normally have lymphatics. However, patients with generalized lymphatic anomaly (GLA) or Gorham-Stout disease (GSD) develop ectopic lymphatics in bone. Despite growing interest in the development of tissue-specific lymphatics, the cellular origin of bone lymphatic endothelial cells (bLECs) is not known and the development of bone lymphatics has not been fully characterized. Here we describe the development of bone lymphatics in mouse models of GLA and GSD. Through lineage tracing experiments, we show that bLECs arise from preexisting Prox1-positive LECs. We show that bone lymphatics develop in a stepwise manner where regional lymphatics grow, breach the periosteum, and then invade bone. We also show that the development of bone lymphatics is impaired in mice that lack osteoclasts. Lastly, we show that rapamycin can suppress the growth of bone lymphatics in our models of GLA and GSD. In summary, we show that bLECs can arise from preexisting LECs and that rapamycin can prevent the growth of bone lymphatics. © 2020. Published by The Company of Biologists Ltd.Continual spermatogenesis relies on the actions of an undifferentiated spermatogonial population that is composed of stem cells and progenitors. Here, using mouse models, we explored the role of RNA binding proteins (RBPs) in regulation of the biological activities of this population. Proteins bound to polyadenylated RNAs in primary cultures of undifferentiated spermatogonia were captured with oligo (dT)-conjugated beads after UV-crosslinking and profiled by proteomics (termed as mRBPome capture), yielding a putative repertoire of 473 RBPs. From this database, the RBP TRIM71 was identified and found to be expressed by stem and progenitor spermatogonia in prepubertal and adult mouse testes. Tissue-specific deletion of TRIM71 in the male germline led to reduction of the undifferentiated spermatogonial population and a block in transition to the differentiati