Sammeta Neeraja, Yu Tun-Tzu, Bose Soma C, McClintock Timothy S
Department of Physiology, Cellular and Molecular Neuroscience of Sensory Systems Training Program, University of Kentucky, Lexington, Kentucky 40536-0298, USA.
J Comp Neurol. 2007 Jun 20;502(6):1138-56. doi: 10.1002/cne.21365.
Olfactory epithelial cells from olfactory marker protein-green fluorescent protein (OMP-GFP) mice were separated by fluorescence-activated cell sorting into a GFP+ sample enriched in mature olfactory sensory neurons (OSNs) and a GFP- sample enriched in all other cells. GeneChip expression profiling of these samples provided a predictive measure of expression in OSNs. Validation tests comparing the ratio of GFP+/GFP- signal intensity against expression patterns from in situ hybridization for 189 mRNAs proved statistically significant and provided probabilities of expression in OSNs scaled according to the signal intensity ratios. These probabilities predict that, among 11,596 mRNAs detected in the GFP+ sample, more than 10,000 are expressed in OSNs. Transcripts and overrepresented categories of mRNAs detected in the GFP+ sample agreed with known properties of OSNs and predict additional properties. For example, ciliogenesis and spermatogenesis were overrepresented, consistent with similarities between OSN cilia and sperm flagella. Chromatin assembly mRNAs were expressed throughout the OSN cell lineage, consistent with the hypothesis that chromatin remodeling plays a role in OSN differentiation. We detected numerous signaling proteins and receptors, such as 30 nonchemosensory G-protein-coupled receptors, including the presynaptic glutamate receptor mGlur4 and the Wnt receptor Fzd3. The largest group of mRNAs, however, was the hundreds of transcriptional regulators that presumably determine the OSN phenotype. The absence of OMP protein in OMP-GFP mice had no detectable effect on mRNA abundance. Within limits prescribed by the nature of microarray data and the in situ hybridization validation, these data should be useful in directing further experiments on OSN function.
通过荧光激活细胞分选技术，从嗅觉标记蛋白-绿色荧光蛋白（OMP-GFP）小鼠中分离出嗅觉上皮细胞，分为富含成熟嗅觉感觉神经元（OSN）的GFP+样本和富含所有其他细胞的GFP-样本。对这些样本进行基因芯片表达谱分析，可预测OSN中的表达情况。将GFP+/GFP-信号强度比值与189种mRNA的原位杂交表达模式进行比较的验证测试具有统计学意义，并根据信号强度比值提供了OSN中表达的概率。这些概率预测，在GFP+样本中检测到的11,596种mRNA中，超过10,000种在OSN中表达。在GFP+样本中检测到的转录本和mRNA的过度表达类别与OSN的已知特性相符，并预测了其他特性。例如，纤毛形成和精子发生过度表达，这与OSN纤毛和精子鞭毛之间的相似性一致。染色质组装mRNA在整个OSN细胞谱系中表达，这与染色质重塑在OSN分化中起作用的假设一致。我们检测到许多信号蛋白和受体，如30种非化学感应G蛋白偶联受体，包括突触前谷氨酸受体mGlur4和Wnt受体Fzd3。然而，最大的一组mRNA是数百种可能决定OSN表型的转录调节因子。OMP-GFP小鼠中OMP蛋白的缺失对mRNA丰度没有可检测到的影响。在微阵列数据的性质和原位杂交验证所规定的范围内，这些数据应有助于指导关于OSN功能的进一步实验。
