Expression of two members of the Wnt family during mouse development–restricted temporal and spatial patterns in the developing neural tube.
Submitted by admin on Thu, 10/14/2010 - 22:44
Title | Expression of two members of the Wnt family during mouse development–restricted temporal and spatial patterns in the developing neural tube. |
Publication Type | Journal Article |
Year of Publication | 1991 |
Authors | Roelink H, Nusse R |
Journal | Genes Dev |
Volume | 5 |
Pagination | 381–388 |
Date Published | Mar |
ISSN | 0890-9369 (Print); 0890-9369 (Linking) |
Abstract | The Wnt gene family encodes a group of cysteine-rich proteins implicated in intercellular signaling during several stages of vertebrate development. This family includes Wnt-1 and Wnt-3, both discovered as activated oncogenes in mouse mammary tumors. Here we describe the molecular cloning of an additional member of the Wnt family, called Wnt-3A, and the spatial and temporal expression pattern of this gene as well as that of its close relative Wnt-3. The putative amino acid sequences of both proteins are almost 90% identical, but in situ hybridization to mouse embryo sections showed highly restricted patterns of expression of Wnt-3 and Wnt-3A, largely in separate areas in the developing nervous system. In the spinal cord Wnt-3 was expressed at low levels in the alar laminae and in the ventral horns, whereas Wnt-3A expression was confined to the roof plate. In the developing brain Wnt-3 was expressed broadly across the dorsal portion of the neural tube with a rostral boundary of expression at the diencephalon. In contrast, Wnt-3A was expressed in a narrow region very close to the midline; expression extended into the bifurcating telencephalon, in a highly localized fashion. Both Wnt-3 and Wnt-3A were expressed in the ectoderm, and Wnt-3A was also expressed in the periumbilical mesenchyme. Characteristic expression patterns of these two closely related genes suggest that Wnt-3 and Wnt-3A play distinct roles in cell-cell signaling during morphogenesis of the developing neural tube. |