Proper control of the temporal onset of cellular differentiation is critical for regulating cell lineage decisions and morphogenesis during development. Pbx homeodomain transcription factors have emerged as important regulators of cellular differentiation. We previously showed, by using antisense morpholino knockdown, that Pbx factors are needed for the timely activation of myocardial different...

Wireless private branch exchange (PBX) system ooers wireless telephone access in an ooce environment. In a WPBX, several base stations are connected to the PBX, and the PBX is connected to the public switched telephone network (PSTN). Since only a small number of telephones are expected to be busy at the same time, the capacity (number of the external lines) between the PBX and the PSTN is typi...

Retinoic acid (RA) induces expression of genes encoding the Hox family of transcription factors, whose differential expression orchestrates developmental programs specifying anterior-posterior structures during embryogenesis. Hox proteins bind DNA as monomers and heterodimers with Pbx proteins. Here we show that RA upregulates Pbx protein abundance coincident with transcriptional activation of ...

Members of the Pbx family are involved in a diverse range of developmental processes including axial patterning and organogenesis. Pbx functions are in part mediated by the interaction of Pbx proteins with members of the Hox and Meis/Prep families. We have identified a fourth mammalian Pbx family member. Pbx4 in the mouse and PBX4 in humans are located on chromosome 8 and chromosome 19, respect...

Hox proteins form complexes with Pbx and Meis cofactors to control gene expression, but the role of Meis is unclear. We demonstrate that Hoxb1-regulated promoters are highly acetylated on histone H4 (AcH4) and occupied by Hoxb1, Pbx, and Meis in zebrafish tissues where these promoters are active. Inhibition of Meis blocks gene expression and reduces AcH4 levels at these promoters, suggesting a ...

Two classes of homeodomain proteins, Hox and Engrailed, have been shown to act in concert with the atypical homeodomain proteins Pbx and extradenticle. We now show that specific residues located within the Pbx homeodomain are essential for cooperative DNA binding with Hox and Engrailed gene products. Within the N-terminal region of the Pbx homeodomain, we have identified a residue that is requi...