New insights in the clockwork mechanism regulating lineage specification: Lessons from the Drosophila nervous system.
BACKGROUND
Powerful transcription factors called fate determinants induce robust differentiation programs in multipotent cells and trigger lineage specification. These factors guarantee the differentiation of specific tissues/organs/cells at the right place and the right moment to form a fully functional organism. Fate determinants are activated by temporal, positional, epigenetic, and post-transcriptional cues, hence integrating complex and dynamic developmental networks. In turn, they activate specific transcriptional/epigenetic programs that secure novel molecular landscapes.


RESULTS
In this review, we use the Drosophila Gcm glial determinant as a model to discuss the mechanisms that allow lineage specification in the nervous system. The dynamic regulation of Gcm via interlocked loops has recently emerged as a key event in the establishment of stable identity. Gcm induces gliogenesis while triggering its own extinction, thus preventing the appearance of metastable states and neoplastic processes.


CONCLUSIONS
Using simple animal models that allow in vivo manipulations provides a key tool to disentangle the complex regulation of cell fate determinants.
Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France; Centre National de la Recherche Scientifique, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, Illkirch, France; Université de Strasbourg, Illkirch, France.
Pierre B
PB
Cattenoz
Angela
A
Giangrande
D000818:Animals; D019070:Cell Lineage / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster; D039902:Multipotent Stem Cells / Q000166:cytology / Q000378:metabolism*; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D029721:Drosophila Proteins; D014157:Transcription Factors
cell fate determinant; feedback loop; glia