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Presenting Author(s) Charalampos Rallis
Abstract Title A potential role for the T-box gene Tbx3 in positioning the forelimb along the rostro-caudal axis of the embryo.
Full author List Charalampos Rallis, Jo Del Buono and Malcolm Logan
Text of abstract

Forelimbs and hindlimbs in vertebrates are formed at defined levels along the rostro-caudal axis of the embryo. The position of the limb-forming regions are thought to be determined by a combinatorial Hox gene code that provides "positional information" to cells of the prospective forelimb and hindlimb regions. Subsequently, interactions between dHand and Gli3 pre-pattern the prospective antero-posterior axis of the limb prior to Shh activity and define the position of the Zone of Polirizing Activity (ZPA).

We present data showing that Tbx3, a T-domain-containing transcriptional repressor may have an important role in positioning the forelimb. Misexpression of forms of Tbx3 lead to an alteration of the wing axial position. The displacement of the wing causes alterations in the migration of myoblasts and the pattern of motor neuron axon innervation of the limb muscles. Moreover, data suggest that genes important in antero-posterior patterning of the developing limbs (dHand/Gli3), during earlier developmental stages are implicated in limb positioning along the rostro-caudal axis of the embryo. Our experiments reveal a genetic interplay between Tbx3, dHand and Gli3 that may act downstream of an axial Hox code and determine the axial position of the limb forming region.
Which session is your work most relevant to: Limb initiation