1st EXPERIMENTAL APPROACHES FROM THE PAPER THAT SUPPORTS A ROLE FOR SHH signaling IN THIS DEVELOPMENTAL EVENT:
- In the Laufer et al paper, in situ hybridization experiments showed Shh promotes expression of downstream genes involved in patterning in limb bud.
- Using embryos ectopically injected with Shh virus, expression of Hoxd genes was visualized via radioactive probes at multiple time points.
- Results show: Shh expression occurred first, followed by Hoxd-11 and -13 at the later time points. The authors concluded that Shh has the ability to PROMOTE DOWNSTREAM Hoxd genes