TY - JOUR
T1 - Bmp activity gradient regulates convergent extension during zebrafish gastrulation
AU - Myers, Dina C.
AU - Sepich, Diane S.
AU - Solnica-Krezel, Lilianna
N1 - Funding Information:
We thank B. Appel, B. Hogan, C. Henry, M. Gannon, F. Marlow, and J. Jessen for critical reading of the manuscript, and members of our lab for discussions and comments. We are indebted to C.-P. Heisenberg for his advice on slb in situ hybridization. We acknowledge B. Heher and J. Clanton for excellent fish care. cDNA clones were provided by S. Amacher, M. Hammerschmidt, H. Takeda, R. Toyama, N. Ueno, and P. Blader, and fish strains were from M. Mullins and M. Halpern. This work is supported by NIH Grant GM55101 (to L.S.K.), who is a Pew Scholar.
PY - 2002/3/1
Y1 - 2002/3/1
N2 - During vertebrate gastrulation, a ventral to dorsal gradient of bone morphogenetic protein (Bmp) activity establishes cell fates. Concomitantly, convergent extension movements narrow germ layers mediolaterally while lengthening them anteroposteriorly. Here, by measuring movements of cell populations in vivo, we reveal the presence of three domains of convergent extension movements in zebrafish gastrula. Ventrally, convergence and extension movements are absent. Lateral cell populations converge and extend at increasing speed until they reach the dorsal domain where convergence speed slows but extension remains strong. Using dorsalized and ventralized mutants, we demonstrate that these domains are specified by the Bmp activity gradient. In vivo cell morphology and behavior analyses indicated that low levels of Bmp activity might promote extension with little convergence by allowing mediolateral cell elongation and dorsally biased intercalation. Further, single cell movement analyses revealed that the high ventral levels of Bmp activity promote epibolic migration of cells into the tailbud, increasing tail formation at the expense of head and trunk. We show that high Bmp activity limits convergence and extension by negatively regulating expression of the wnt11 (silberblick) and wnt5a (pipetail) genes, which are required for convergent extension but not cell fate specification. Therefore, during vertebrate gastrulation, a single gradient of Bmp activity, which specifies cell fates, also regulates the morphogenetic process of convergent extension.
AB - During vertebrate gastrulation, a ventral to dorsal gradient of bone morphogenetic protein (Bmp) activity establishes cell fates. Concomitantly, convergent extension movements narrow germ layers mediolaterally while lengthening them anteroposteriorly. Here, by measuring movements of cell populations in vivo, we reveal the presence of three domains of convergent extension movements in zebrafish gastrula. Ventrally, convergence and extension movements are absent. Lateral cell populations converge and extend at increasing speed until they reach the dorsal domain where convergence speed slows but extension remains strong. Using dorsalized and ventralized mutants, we demonstrate that these domains are specified by the Bmp activity gradient. In vivo cell morphology and behavior analyses indicated that low levels of Bmp activity might promote extension with little convergence by allowing mediolateral cell elongation and dorsally biased intercalation. Further, single cell movement analyses revealed that the high ventral levels of Bmp activity promote epibolic migration of cells into the tailbud, increasing tail formation at the expense of head and trunk. We show that high Bmp activity limits convergence and extension by negatively regulating expression of the wnt11 (silberblick) and wnt5a (pipetail) genes, which are required for convergent extension but not cell fate specification. Therefore, during vertebrate gastrulation, a single gradient of Bmp activity, which specifies cell fates, also regulates the morphogenetic process of convergent extension.
KW - Convergence
KW - Dorsoventral patterning
KW - Extension
KW - Morphogenesis
KW - Morphology
UR - http://www.scopus.com/inward/record.url?scp=0036499809&partnerID=8YFLogxK
U2 - 10.1006/dbio.2001.0523
DO - 10.1006/dbio.2001.0523
M3 - Article
C2 - 11846479
AN - SCOPUS:0036499809
SN - 0012-1606
VL - 243
SP - 81
EP - 98
JO - Developmental Biology
JF - Developmental Biology
IS - 1
ER -