Organizer-derived Bmp2 is required for the formation of a correct Bmp activity gradient during embryonic development.
Bone morphogenetic proteins (Bmps) control dorsoventral patterning of vertebrate embryos through the establishment of a ventrodorsal gradient of the activated downstream cytoplasmic effectors Smad1/5/8. Some Bmp ligands are expressed in the ventral and lateral regions and in the organizer during gastrulation of the embryo, but it remains unclear how organizer-derived Bmps contribute to total Bmp ligand levels and to the establishment of the correct phospho-Smad1/5/8 gradient along the ventrodorsal axis. Here we demonstrate that interference with organizer-specific Bmp2b signalling in zebrafish embryos alters the phospho-Smad1/5/8 gradient throughout the ventrodorsal axis, elevates the levels of the Bmp antagonist Chordin and dorsalizes the embryos. Moreover, we show that organizer-derived Bmp2b represses chordin transcription in the organizer and contributes to the control of the Chordin gradient. Combining these experimental results with simulations of Bmp's reaction-diffusion dynamics, our data indicate that organizer-produced Bmp2b is required for the establishment and maintenance of a Bmp activity gradient and for appropriate embryonic dorsoventral patterning during gastrulation.
1] State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China [2].
Yu
Y
Xue
1] Key Laboratory of Animal Ecology and Conservation Biology, Centre for Computational Biology and Evolution, Chinese Academy of Sciences, Beijing 100101, China [2].
Xiudeng
X
Zheng
School of Life Sciences, Tsinghua University, Beijing 100084, China.
Lei
L
Huang
State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China.
Pengfei
P
Xu
State Key Laboratory of Biomembrane and Membrane Engineering, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
Yuanqing
Y
Ma
School of Life Sciences, Tsinghua University, Beijing 100084, China.
Zheying
Z
Min
School of Life Sciences, Tsinghua University, Beijing 100084, China.
Qinghua
Q
Tao
Key Laboratory of Animal Ecology and Conservation Biology, Centre for Computational Biology and Evolution, Chinese Academy of Sciences, Beijing 100101, China.
Yi
Y
Tao
1] State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China [2] State Key Laboratory of Biomembrane and Membrane Engineering, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
Anming
A
Meng
D000818:Animals; D015153:Blotting, Western; D019521:Body Patterning / Q000502:physiology*; D055396:Bone Morphogenetic Protein 2 / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D017931:DNA Primers / Q000235:genetics; D005455:Fluorescent Antibody Technique; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D006023:Glycoproteins / Q000378:metabolism; D017403:In Situ Hybridization; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D008156:Luciferases; D018613:Microscopy, Confocal; D008954:Models, Biological; D020897:Organizers, Embryonic / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D051785:Smad Proteins / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology*; D029961:Zebrafish Proteins / Q000378:metabolism*
D055396:Bone Morphogenetic Protein 2; D017931:DNA Primers; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D051785:Smad Proteins; D029961:Zebrafish Proteins; C405936:bmp2b protein, zebrafish; C054234:chordin; D008156:Luciferases