|
|
|
|
|
|
|
||
J. Cell Biol.,
Volume 143, Number 6, December 14, 1998 1713-1723
5 Chain
* Department of Medicine, Renal Division and Laminins are the major noncollagenous glycoproteins of all basal laminae (BLs). They are Department of Anatomy and Neurobiology, Washington University School of
Medicine, St. Louis, Missouri 63110
/
/
heterotrimers assembled from 10 known chains, and
they subserve both structural and signaling roles. Previously described mutations in laminin chain genes result in diverse disorders that are manifested postnatally and
therefore provide little insight into laminin's roles in
embryonic development. Here, we show that the laminin 5 chain is required during embryogenesis. The 5
chain is present in virtually all BLs of early somite stage embryos and then becomes restricted to specific BLs as
development proceeds, including those of the surface
ectoderm and placental vasculature. BLs that lose 5
retain or acquire other chains. Embryos lacking laminin 5 die late in embryogenesis. They exhibit multiple
developmental defects, including failure of anterior neural tube closure (exencephaly), failure of digit septation (syndactyly), and dysmorphogenesis of the placental labyrinth. These defects are all attributable to
defects in BLs that are 5 positive in controls and that
appear ultrastructurally abnormal in its absence. Other
laminin chains accumulate in these BLs, but this compensation is apparently functionally inadequate. Our results identify new roles for laminins and BLs in diverse developmental processes.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
