Friedel R H, Schnürch H, Stubbusch J, Barde Y A
Abteilung Neurobiochemie, Max-Planck-Institut für Psychiatrie, Am Klopferspitz 18a, D-82152 Martinsried, Germany.
Proc Natl Acad Sci U S A. 1997 Nov 11;94(23):12670-5. doi: 10.1073/pnas.94.23.12670.
The neurotrophins nerve growth factor (NGF) and neurotrophin-3 (NT3) support the survival of subpopulations of primary sensory neurons with defined and distinct physiological characteristics. Only a few genes have been identified as being differentially expressed in these subpopulations, and not much is known about the nature of the molecules involved in the processing of sensory information in NGF-dependent nociceptive neurons or NT3-dependent proprioceptive neurons. We devised a simple dorsal root ganglion (DRG) explant culture system, allowing the selection of neuronal populations preferentially responsive to NGF or NT3. The reliability of this assay was first monitored by the differential expression of the NGF and NT3 receptors trkA and trkC, as well as that of neuropeptides and calcium-binding proteins. We then identified four differentially expressed sodium channels, two enriched in the NGF population and two others in the NT3 population. Finally, using an optimized RNA fingerprinting protocol, we identified 20 additional genes, all differentially expressed in DRG explants cultured with NGF or NT3. This approach thus allows the identification of large number of genes expressed in subpopulations of primary sensory neurons and opens the possibility of studying the molecular mechanisms of nociception and proprioception.
神经营养因子神经生长因子（NGF）和神经营养因子-3（NT3）支持具有特定且不同生理特征的初级感觉神经元亚群的存活。仅有少数基因被确定在这些亚群中差异表达，对于参与NGF依赖的伤害性感受神经元或NT3依赖的本体感觉神经元感觉信息处理的分子性质，我们了解得并不多。我们设计了一种简单的背根神经节（DRG）外植体培养系统，能够选择对NGF或NT3优先产生反应的神经元群体。该检测方法的可靠性首先通过NGF和NT3受体trkA和trkC以及神经肽和钙结合蛋白的差异表达来监测。然后，我们鉴定出四个差异表达的钠通道，其中两个在NGF群体中富集，另外两个在NT3群体中富集。最后，使用优化的RNA指纹图谱方案，我们鉴定出另外20个基因，它们在与NGF或NT3一起培养的DRG外植体中均差异表达。因此，这种方法能够鉴定在初级感觉神经元亚群中表达的大量基因，并为研究伤害感受和本体感觉的分子机制开辟了可能性。
