Expression of a Constitutively Active Type I BMP Receptor Using a Retroviral Vector Promotes the Development of Adrenergic Cells in Neural Crest Cultures

Abstract

Previous work has demonstrated that the bone morphogenetic proteins (BMP)-2, BMP-4, and BMP-7 can promote the development of tyrosine hydroxylase (TH)-positive and catecholamine-positive cells in quail trunk neural crest cultures. In the present work, we showed that mRNA for the type I bone morphogenetic protein receptor IA (BMPR-IA) was present in neural crest cells grown in the absence or presence of BMP-4. We have used a replication-competent avian retrovirus to express a constitutively active form of BMPR-IA in neural crest cells in culture. Cultures grown in the absence of BMP-4 and infected with retrovirus containing a construct encoding this activated BMPR-IA developed five times more TH-immunoreactive and catecholamine-positive cells than uninfected control cultures or cultures infected with virus bearing the wild-type BMPR-IA cDNA. The number of TH-positive cells which developed was dependent on the concentration of virus bearing the activated receptor cDNA used in the experiments. Most TH-positive cells which developed also contained viral p19 protein. Total cell number was not affected by infection with the virus containing the activated receptor construct. The effect of the activated receptor was phenotype-specific since infection with the virus bearing the activated receptor cDNA did not alter the number or morphology of microtubule-associated protein (MAP)2-immunoreactive cells, which are distinct from the TH-positive cell population. These findings are consistent with the observation that MAP2-positive cells are not affected by the presence of BMP-4. Taken together, these results suggest that activity of BMPR-IA is an important element in promoting the development of the adrenergic phenotype in neural crest cultures.

High-Level Activation of Cyclic AMP Signaling Attenuates Bone Morphogenetic Protein 2-Induced Sympathoadrenal Lineage Development and Promotes Melanogenesis in Neural Crest Cultures

“…Extracellular signaling molecules that have been implicated to date in NC lineage segregation include the Wnt proteins (19,20,35), bone morphogenetic proteins (BMP2, -4, -7) (53,65,66,67), transforming growth factors ␤1 to ␤3 (59), and glial growth factor 2 (60). Known mechanistic aspects of NC lineage segregation include the instructive role of BMPs in SA lineage development (56,59) in mediating transcriptional induction of proneural transcription factors Ash1 and phox2a/2b (43,61).…”

Cyclic AMP Signaling Functions as a Bimodal Switch in Sympathoadrenal Cell Development in Cultured Primary Neural Crest Cells

“…By contrast, forskolin and ␤-adrenergic ligands were shown to regulate the expression of the quail TH gene and promote the development of SA cells (9). More recent investigations also demonstrated that BMP-2, -4, and -7/OP-1 dramatically stimulate SA cell development (55,68,70) and established the causal link of a BMP ligand on the generation of SA cells (69).…”

“…BMP-2, -4, and -7 are produced by endothelial cells of the aorta as crest cells form the sympathetic trunks and adrenal gland primordia (55,58), suggesting that these factors are relevant to SA cell development in vivo. Moreover, the causal link of BMP-2 to SA cell development has been demonstrated by expression of a constitutively active mutant of the BMP type I receptor in cultured crest cells (69). Although the mechanism of regulation has not been elucidated, BMPs induce the expression of genes essential to SA lineage determination.…”

BMP signaling regulates sympathetic nervous system development through Smad4-dependent and -independent pathways

“…Overexpression of a constitutively active form of Alk3 increases catecholaminergic differentiation in NC cultures (Varley et al, 1998), suggesting that BMP signaling during SNS development occurs through the Alk3 receptor. To determine if BMP signaling is essential for NC cells during mouse SNS development, we conditionally deleted Alk3 in NC cells, using the Wnt1-Cre deleter line, while simultaneously tracing NC cells using the R26R allele (Mao et al, 1999) (Fig.…”