... protein can induce both active cell migration and convergent extension. We find that Xbra , a transcription factor necessary for convergent extension, actively inhibits cell migration, both in animal cap explant assays and in the endogenous dorsal mesoderm. In addition, Xbra appears to inhibit cell...

... pathways have been identified in Xenopus promoters, it is not yet understood what defines the sharp borders that restrict expression to a specific tissue. Here we use transgenic frog embryos to study the spatial and temporal regulation of the Xbra promoter. Deletion analysis and point mutations in putative...

... convergent extension movements associated with dorsal mesoderm induction and the expression of goosecoid , a dorsal-specific gene, but is without effect on expression of a generic mesodermal marker, Xbra . All of these effects of a PI cycle-stimulating receptor are the opposites of those previously reported...

... with bFGF and noggin express Xslu but not NCAM although the mesoderm marker Xbra is also expressed. Explants treated with noggin alone express NCAM only. An indication that induction of the neural plate border is regulated independently of the neural plate is obtained from experiments using ultraviolet...

... and Xwnt-8 , in Xenopus gastrulae in which cell-cell communication, and therefore mesoderm induction, has been prevented by frequent cell dispersion. Although neither the early panmesodermal marker Xbra nor the muscle-specific α-actin gene were activated under these conditions, goosecoid and Xwnt-8 were...