International Mammalian Genome Society

The 16th International Mouse Genome Conference (2002)

Plenary Presentations * Oral Presentations *
Poster Presentations: Complex Genetics and Disease Modifiers * Developmental Genetics * Functional Genomics * Gene Discovery * Genetic Manipulations to Alter Gene Function * Mouse Models: Human Disease and Pharmacogenetics * Sequence Annotation and Comparative Analysis of Genomes *
Attendees * Sponsors * Table of Contents * Photographs * Awards

Oral Presentation

Tuesday 19 November

11:00 - 11:15 HRS

MESD PROMOTES SUBCELLULAR LOCALIZATION OF THE WNT CO-RECEPTORS LRP5/6

L Lee
State University of New York at Stony Brook

Co-Authors:, Hsieh JC, Zhang L, Wefer S, Brown K, Holdener, BC.
Institutions: State University of New York at Stony Brook

Mouse embryos lacking the mesoderm development (mesd) deletion interval fail to form mesoderm or a primitive streak and do not survive to term. The mesd gene is ubiquitously expressed and encodes a novel ER resident protein.  Biochemical and cell culture studies suggest that the Mesd protein promotes surface localization of the Wnt co-receptors LRP5 and 6.  Failure to form a primitive streak in mesd mutant embryos results from an inability to maintain expression of Nodal and Wnt3 in the proximal epiblast, suggesting that Wnt signals are required for activation or maintenance of Nodal in the proximal epiblast. In contrast, anterior visceral endoderm and anterior epiblast gene expression is expanded. These results demonstrate that establishment of the A/P axis is dependent upon antagonism between head and trunk signals.  We are currently investigating the mechanism of Mesd function in the cell.