Specification ofDrosophilamotoneuron identity by the combinatorial action of POU and LIM-HD factors

• DOI: 10.1242/dev.01418
• Publication Date: 2004-10-07T00:13:55Z
• Authors: Sarah J. Certel; Stefan Thor
• Keywords: POU domain; Immunoglobulin superfamily; Ventral nerve cord

In both vertebrates and invertebrates, members of the LIM-homeodomain (LIM-HD) family transcription factors act in combinatorial codes to specify motoneuron subclass identities. developing Drosophila embryo, LIM-HD Islet (Tailup) Lim3, set subclasses that innervate ventral muscle targets. However, as several express this code alone cannot explain how these groups are further differentiated. To identify additional may refine code, we have analyzed expression POU genes embryonic nerve cord. We find class III protein, Drifter (Ventral veinless), is co-expressed with Lim3 specifically ISNb subclass. Loss-of-function misexpression studies demonstrate requires confer target specificity between TN subclasses. begin elucidate molecules downstream examined involvement Beaten path (Beat) immunoglobulin-containing cell-adhesion molecules. beat Ic genetically interacts islet can also rescue fasciculation defects observed mutants. These results suggest context, axon selection through actions IgSF call-adhesion