... the embryo. * Author for correspondence (e-mail: [email protected] ) 24 03 1998 06 05 1998 © 1998 by Company of Biologists 1998 Sclerotome Chick Determination Pax-1 Somite Cartilage The embryonic precursors of three diverse cellular lineages are contained...

..., respectively, by the expression of MyoD and Pax-1 genes. In contrast, Pax-3 transcripts, normally present in cells giving rise to hypaxial muscles, are preserved in the excised embryos. Backgrafting either the ventral neural tube or the notochord allows survival of MyoD - and Pax-1 -expressing cells. Similarly...

... at the appropriate position as a mass of mesenchymal cells. However, ectopic Pax-1 expression was observed in the proatlas anlage whereas the anterior boundary of Pax-1 expression in the ventral paraxial mesoderm of wild-type embryo was at C1/C2 boundary (Arrows in Fig. 7A,C ). Therefore the anterior boundary...

... differentiation of the surrounding pharyngeal arch and pouch tissues. Hoxa-3 mutant mice are athymic and show thyroid hypoplasia. Thymus development is first evident as an expansion of mesenchymal neural crest in the posterior part of the 3rd pharyngeal pouch. Prior to this expansion, a marked reduction in pax-1...

...Johan Wallin; Jörg Wilting; Haruhiko Koseki; Rüdiger Fritsch; Bodo Christ; Rudi Balling ABSTRACT Previous studies have identified a single amino-acid substitution in the transcriptional regulator Pax-1 as the cause of the mouse skeletal mutant undulated ( un ). To evaluate the role of Pax-1...

... ), a sclerotome mutant. Double mutants between Sd and un alleles show an increase in the severity of the defects, mainly in the ventral parts of the vertebrae. We also show that part of the Sd phenotype is strikingly similar to that of the un alleles. As un is known to be caused by a mutation in the Pax-1 gene...