“
“The various organs of the body harbor blood vessel networks that display unique structural and functional features; however, the mechanisms that control organ-specific vascular development and physiology remain mostly unknown. In the developing mouse brain, alpha v beta 8 integrin-mediated TGF-beta activation

and signaling is essential for normal blood vessel growth and sprouting. Whether integrins activate TGF-beta signaling pathways in vascular endothelial cells (ECs), neural cells, or both, has yet to be determined. Here, we have generated and characterized mice in which TGF-beta receptors are specifically deleted in neuroepithelial cells via Nestin-Cre, or in ECs via a novel Cre transgenic strain (Alk1(GFPCre)) in which Cre is expressed under control of the endogenous activin receptor-like kinase 1 (Alk1) promoter. We report that deletion of Tgfbr2 in the AZD4547 cost neuroepithelium does not impact

brain vascular PI3K inhibitor development. In contrast, selective deletion of the Tgfbr2 or Alk5 genes in ECs result in embryonic lethality because of brain-specific vascular pathologies, including blood vessel morphogenesis and intracerebral hemorrhage. These data reveal for the first time that alpha v beta 8 integrin-activated TGF-beta s regulate angiogenesis in the developing brain Selleckchem MLN2238 via paracrine signaling to ECs. Laboratory Investigation (2011) 91, 1554-1563; doi: 10.1038/labinvest.2011.124; published

online 29 August 2011″
“The unique segregation of homologs, rather than sister chromatids, at the first meiotic division requires the formation of crossovers (COs) between homologs by meiotic recombination in most species. Crossovers do not form at random along chromosomes. Rather, their formation is carefully controlled, both at the stage of formation of DNA double-strand breaks (DSBs) that can initiate COs and during the repair of these DSBs. Here, we review control of DSB formation and two recently recognized controls of DSB repair: CO homeostasis and CO invariance. Crossover homeostasis maintains a constant number of COs per cell when the total number of DSBs in a cell is experimentally or stochastically reduced. Crossover invariance maintains a constant CO density (COs per kb of DNA) across much of the genome despite strong DSB hotspots in some intervals. These recently uncovered phenomena show that CO control is even more complex than previously suspected.”
“Sensorimotor representations in the brain encode the sensory and motor aspects of one’s own bodily activity. It is highly debated whether sensorimotor representations are the core basis for the representation of action-related knowledge and, in particular, action words, such as verbs.