| Autor: |
Koneru SL; Department of Life Sciences, Imperial College, London, SW7 2AZ, UK., Quah FX; Department of Life Sciences, Imperial College, London, SW7 2AZ, UK., Ghose R; Department of Life Sciences, Imperial College, London, SW7 2AZ, UK.; Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, 08003, Barcelona, Spain., Hintze M; Department of Life Sciences, Imperial College, London, SW7 2AZ, UK., Gritti N; AMOLF, Science Park 104, 1098 XG, Amsterdam, the Netherlands., van Zon JS; AMOLF, Science Park 104, 1098 XG, Amsterdam, the Netherlands., Barkoulas M; Department of Life Sciences, Imperial College, London, SW7 2AZ, UK. m.barkoulas@imperial.ac.uk. |
| Abstrakt: |
Developmental patterning in Caenorhabditis elegans is known to proceed in a highly stereotypical manner, which raises the question of how developmental robustness is achieved despite the inevitable stochastic noise. We focus here on a population of epidermal cells, the seam cells, which show stem cell-like behaviour and divide symmetrically and asymmetrically over post-embryonic development to generate epidermal and neuronal tissues. We have conducted a mutagenesis screen to identify mutants that introduce phenotypic variability in the normally invariant seam cell population. We report here that a null mutation in the fusogen eff-1 increases seam cell number variability. Using time-lapse microscopy and single molecule fluorescence hybridisation, we find that seam cell division and differentiation patterns are mostly unperturbed in eff-1 mutants, indicating that cell fusion is uncoupled from the cell differentiation programme. Nevertheless, seam cell losses due to the inappropriate differentiation of both daughter cells following division, as well as seam cell gains through symmetric divisions towards the seam cell fate were observed at low frequency. We show that these stochastic errors likely arise through accumulation of defects interrupting the continuity of the seam and changing seam cell shape, highlighting the role of tissue homeostasis in suppressing phenotypic variability during development. |
