Follow the mRNA: a new model for Bicoid gradient formation.
Morphogens are molecules that specify cell fate in a concentration-dependent manner. A classic example is the Bicoid (BCD) protein, for which the prevailing model is that translation of bcd mRNA occurs from a point source at the anterior pole of the Drosophila melanogaster embryo followed by diffusion to produce a protein gradient. This model has been challenged by experiments showing that the diffusion rate of BCD is too slow to establish the protein gradient. The work described in a recent paper has solved this conundrum by demonstrating that a bcd mRNA gradient prefigures the BCD protein gradient.
Lipshitz
Howard D
HD
University of Toronto, Department of Molecular Genetics, Hospital for Sick Children Research Institute Program in Developmental and Stem Cell Biology, Toronto, Ontario, Canada. howard.lipshitz@utoronto.ca
D000818:Animals; D004058:Diffusion; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000166:cytology / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000378:metabolism*; D008954:Models, Biological; D034443:RNA Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism*
D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D015534:Trans-Activators; C056478:bcd protein, Drosophila