BMP-4 inhibits neural differentiation of murine embryonic stem cells.
Members of the transforming growth factor-beta superfamily, including bone morphogenetic protein 4 (BMP-4), have been implicated as regulators of neuronal and glial differentiation. To test for a possible role of BMP-4 in early mammalian neural specification, we examined its effect on neurogenesis in aggregate cultures of mouse embryonic stem (ES) cells. Compared to control aggregates, in which up to 20% of the cells acquired immunoreactivity for the neuron-specific antibody TuJ1, aggregates maintained for 8 days in serum-free medium containing BMP-4 generated 5- to 10-fold fewer neurons. The action of BMP-4 was dose dependent and restricted to the fifth through eighth day in suspension. In addition to the reduction in neurons, we observed that ES cell cultures exposed to BMP-4 contained fewer cells that were immunoreactive for glial fibrillary acidic protein or the HNK-1 neural antigen. Furthermore, under phase contrast, cultures prepared from BMP-4-treated aggregates contained a significant proportion of nonneuronal cells with a characteristic flat, elongated morphology. These cells were immunoreactive for antibodies to the intermediate filament protein vimentin; they were rare or absent in control cultures. Treatment with BMP-4 enhanced the expression of the early mesodermal genes brachyury and tbx6 but had relatively little effect on total cell number or cell death. Coapplication of the BMP-4 antagonist noggin counteracted the effect of exogenous BMP-4, but noggin alone had no effect on neuralization in either the absence or presence of retinoids. Collectively, our results suggest that BMP-4 can overcome the neuralizing action of retinoic acid to enhance mesodermal differentiation of murine ES cells.
Finley
M F
MF
Department of Cell Biology and Physiology and Program in Neuroscience, Washington University Medical School, 660 South Euclid Avenue, St. Louis, Missouri 63110, USA.
Devata
S
S
Huettner
J E
JE
D000818:Animals; D000906:Antibodies / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002449:Cell Aggregation / Q000187:drug effects; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D017931:DNA Primers / Q000235:genetics; D004622:Embryo, Mammalian / Q000166:cytology; D004627:Embryonic Induction / Q000187:drug effects; D005455:Fluorescent Antibody Technique; D005904:Glial Fibrillary Acidic Protein / Q000187:drug effects / Q000276:immunology; D008648:Mesoderm / Q000187:drug effects; D051379:Mice; D009474:Neurons / Q000276:immunology / Q000378:metabolism*; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects*; D013997:Time Factors
D000906:Antibodies; D019485:Bone Morphogenetic Proteins; D017931:DNA Primers; D005904:Glial Fibrillary Acidic Protein; D012333:RNA, Messenger