title: Live imaging of individual cell divisions in mouse neuroepithelium shows asymmetry in cilium formation and Sonic hedgehog response.
abstract: BACKGROUND
  Primary cilia are microtubule-based sensory organelles that play important roles in developmental signaling pathways. Recent work demonstrated that, in cell culture, the daughter cell that inherits the older mother centriole generates a primary cilium and responds to external stimuli prior to its sister cell. This asynchrony in timing of cilia formation could be especially critical during development as cell divisions are required for both differentiation and maintenance of progenitor cell niches.
  
  
  METHODS
  Here we integrate several fluorescent markers and use ex vivo live imaging of a single cell division within the mouse E8.5 neuroepithelium to reveal both the formation of a primary cilium and the transcriptional response to Sonic hedgehog in the daughter cells.
  
  
  RESULTS
  We show that, upon cell division, cilia formation and the Sonic hedgehog response are asynchronous between the daughter cells.
  
  
  CONCLUSIONS
  Our results demonstrate that we can directly observe single cell divisions within the developing neuroepithelium and concomitantly monitor cilium formation or Sonic hedgehog response. We expect this method to be especially powerful in examining whether cellular behavior can lead to both differentiation and maintenance of cells in a progenitor niche.
authors.affiliation: Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA ; on leave from Department of Experimental Embryology, Polish Academy of Sciences, 05-552 Wolka Kosowska, Poland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Piotrowska-Nitsche
authors.forename: Tamara
authors.initials: T
authors.lastname: Caspary
keywords: Shh; cell division; ex vivo live imaging; imaging neuroepithelium; primary cilia