|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
First published online 23 April 2003
doi: 10.1242/jcs.00445
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Research Article |
subunit cytoplasmic tails in vivo
Department of Cell Biology, University of Virginia School of Medicine, PO Box 800732, Charlottesville, VA 22908, USA
* Author for correspondence (e-mail: desimone{at}virginia.edu)
Accepted 27 February 2003
Cell adhesion to fibronectin (FN) is crucial for early vertebrate
morphogenesis. In Xenopus gastrulae, several distinct
integrin-dependent adhesive behaviors can be identified: adhesion of cells to
FN, assembly of FN fibrils, and initiation of cell spreading and migration in
response to mesoderm inducing signals. We have taken a chimeric integrin
approach to investigate the role of the integrin
cytoplasmic tail in
the specification of these developmentally significant adhesive functions.
Cytoplasmic tail-deleted
4 constructs and
4-ectodomain/
-cytoplasmic tail chimeras were generated and
expressed in whole embryos. Normal gastrula cells lack integrin
4 and,
correspondingly, are unable to adhere to the
4 ligand, the V-region of
FN. The ability of
4 constructs to promote adhesive behaviors was
established by placing tissue explants or dissociated cells on an FN V-region
fusion protein that lacks the RGD (Arg-Gly-Asp)/synergy sites or treating
whole embryos with antibodies that block endogenous integrin-FN interactions.
We found that each
4 cytoplasmic domain deletion mutant and
-tail chimera examined could support cell attachment; however, activin
induction-dependent cell spreading, mesoderm cell and explant motility, and
the ability to assemble FN matrix on the blastocoel roof varied with specific
subunit tail sequences. These data suggest that
cytoplasmic
tail signaling and changes in integrin activation state can regulate a variety
of developmentally significant adhesive behaviors in both space and time.
Key words: Integrin, Cell migration, Cell adhesion, Xenopus, Fibronectin
This article has been cited by other articles:
![]() |
K. A. Kragtorp and J. R. Miller Regulation of somitogenesis by Ena/VASP proteins and FAK during Xenopus development Development, February 15, 2006; 133(4): 685 - 695. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Huang, L. C. Bridges, and J. M. White Selective Modulation of Integrin-mediated Cell Migration by Distinct ADAM Family Members Mol. Biol. Cell, October 1, 2005; 16(10): 4982 - 4991. [Abstract] [Full Text] [PDF] |
||||