Tbx3 can alter limb position along the rostrocaudal axis of the developing embryo

C. Rallis
2005 Development  
Embryos Eggs (Needle's farm, Winter's farm, The Poultry Farm) were incubated at 37°C and staged according to Hamburger-Hamilton (HH) (Hamburger and Hamilton, 1951) . Retrovirus production and embryo infection Production of retroviral supernatants were carried out as described previously . Two full-length Tbx3 viruses were produced; one includes amino acid residues 1-732 the other amino acid 15-732 of the predicted protein (AF033669). Both forms produced identical results. Tbx3 EN contains amino
more » ... acids 15-289 of Tbx3, which spans the N terminus and DNA-binding T-domain, fused to the engrailed repressor domain (Jaynes and O'Farrell, 1991). Tbx3 VP16 contains the same residues fused to two VP16 activation The limbs of the vertebrate embryo form at precise locations along the body and these positions are fixed across different species. The mechanisms that control this process are not understood. Ectopic expression of Tbx3, a transcriptional repressor that belongs to the Tbx2/3/4/5 subfamily of T-box transcriptional regulators, in the forelimb results in a rostral shift in the position of the limb along the main body axis. By contrast, a transcriptional activator form of Tbx3 shifts the limb to more caudal locations. We also show that dHand and Gli3, genes previously implicated in anteroposterior pre-patterning of the limb-forming region, are also involved in refining the position of the limbs. Our data suggest a new role for Tbx3 in positioning the limb along the main body axis through a genetic interplay between dHand and Gli3.
doi:10.1242/dev.01787 pmid:15790970 fatcat:fdmylo75ajhmfbet4cqa73brpy