McPherson C E, Varley J E, Maxwell G D
Department of Anatomy, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, Connecticut 06030-340512, USA.
Dev Biol. 2000 May 1;221(1):220-32. doi: 10.1006/dbio.2000.9684.
We have investigated the expression and regulation of the mRNAs for the type I BMP receptors, BMPR-IA and BMPR-IB, in quail embryos in vivo and in neural crest cultures in vitro. BMPR-IB mRNA was expressed in the primordial sympathetic ganglia at stage 17, soon after the first expression of Cash-1 mRNA, the avian homolog of the Drosophila transcription factor achaete-scute. BMP-4 mRNA was detected in the dorsal aorta at stage 17, coincident with BMPR-IB mRNA expression in the sympathetic ganglia. BMPR-IA mRNA was first expressed in the sympathetic ganglia at stage 18. Moreover, BMP-4 ligand mRNA was detected in the sympathetic ganglia starting at stage 18. BMPR-IA and BMPR-IB were differentially regulated in cultured neural crest cells. BMPR-IB was expressed in primary outgrowths of neural crest cells but was downregulated after primary outgrowths were harvested and replated in secondary cultures. In secondary cultures of neural crest cells, exogenous BMP-2 and BMP-4 increased the expression of BMPR-IA but decreased the expression of BMPR-IB. The expression of both type I BMP receptors was inhibited by exogenous TGF-beta1. Our results suggest distinct roles for BMPR-IA and BMPR-IB in the development of the sympathoadrenal phenotype from cells of the neural crest.
我们研究了I型骨形态发生蛋白受体BMPR-IA和BMPR-IB的mRNA在鹌鹑胚胎体内以及体外神经嵴培养物中的表达和调控。BMPR-IB mRNA在第17阶段的原始交感神经节中表达，在Cash-1 mRNA（果蝇转录因子achaete-scute的禽类同源物）首次表达后不久。在第17阶段，在背主动脉中检测到BMP-4 mRNA，与交感神经节中BMPR-IB mRNA的表达一致。BMPR-IA mRNA在第18阶段首次在交感神经节中表达。此外，从第18阶段开始在交感神经节中检测到BMP-4配体mRNA。在培养的神经嵴细胞中，BMPR-IA和BMPR-IB受到不同的调控。BMPR-IB在神经嵴细胞的初级生长中表达，但在收获初级生长并重新接种到二级培养物后被下调。在神经嵴细胞的二级培养物中，外源性BMP-2和BMP-4增加了BMPR-IA的表达，但降低了BMPR-IB的表达。两种I型BMP受体的表达均受到外源性TGF-β1的抑制。我们的结果表明，BMPR-IA和BMPR-IB在神经嵴细胞向交感肾上腺表型发育中具有不同的作用。
