The anatomy of organogenesis: Novel solutions to old problems

Understanding anatomical aspects of mammalian organ development, in both normal and mutant animals, is important for basic biology and also for regenerative medicine and tissue engineering. The size and complexity of developing organs, together with variations in their detailed anatomy, has made the obtaining of high-resolution time-courses of anatomical change difficult to obtain. The fact that organ development tends to use the same genes as early embryogenesis also makes genetic manipulation difficult, as so many mutant embryos die before organogenesis begins. These problems have seriously hampered the study of organogenesis. Here, we describe three significant advances that promise solutions: (1) the production of GFP-reporter mice that can be used for high-resolution live-imaging of small tissues as they grow, (2) RNA interference, which allows the manipulation of specific genes at any stage of organ development, and (3) optical projection tomography, which allows medium-resolution three-dimensional images of complete embryos to be obtained easily. We finish by looking ahead to the prospects of uniting these three technologies to allow accurate, high-throughput screening of mutants and automated comparison of biological data with computer predictions.