BMP-4 inhibits neural differentiation of murine embryonic stem cells

✍ Scribed by Finley, Michael F. A. ;Devata, Sandeep ;Huettner, James E.

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 677 KB
• Volume: 40
• Category: Article
• ISSN: 0022-3034
• DOI: 10.1002/(sici)1097-4695(19990905)40:3<271::aid-neu1>3.0.co;2-c

✦ Synopsis

Members of the transforming growth

factor-␤ 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 serumfree 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.