Chatzidaki Anna, Fouillet Antoine, Li Jingling, Dage Jeffrey, Millar Neil S, Sher Emanuele, Ursu Daniel
Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom.
Lilly Research Centre, Eli Lilly and Company, Windlesham, Surrey, United Kingdom.
PLoS One. 2015 Apr 23;10(4):e0125116. doi: 10.1371/journal.pone.0125116. eCollection 2015.
Neurons derived from human induced pluripotent stem cells (iPSCs) represent a potentially valuable tool for the characterisation of neuronal receptors and ion channels. Previous studies on iPSC-derived neuronal cells have reported the functional characterisation of a variety of receptors and ion channels, including glutamate receptors, γ-aminobutyric acid (GABA) receptors and several voltage-gated ion channels. In the present study we have examined the expression and functional properties of nicotinic acetylcholine receptors (nAChRs) in human iPSC-derived neurons. Gene expression analysis indicated the presence of transcripts encoding several nAChR subunits, with highest levels detected for α3-α7, β1, β2 and β4 subunits (encoded by CHRNA3-CHRNA7, CHRNB1, CHRNB2 and CHRNB4 genes). In addition, similarly high transcript levels were detected for the truncated dupα7 subunit transcript, encoded by the partially duplicated gene CHRFAM7A, which has been associated with psychiatric disorders such as schizophrenia. The functional properties of these nAChRs have been examined by calcium fluorescence and by patch-clamp recordings. The data obtained suggest that the majority of functional nAChRs expressed in these cells have pharmacological properties typical of α7 receptors. Large responses were induced by a selective α7 agonist (compound B), in the presence of the α7-selective positive allosteric modulator (PAM) PNU-120596, which were blocked by the α7-selective antagonist methyllycaconitine (MLA). In addition, a small proportion of the neurons express nAChRs with properties typical of heteromeric (non-α7 containing) nAChR subtypes. These cells therefore represent a great tool to advance our understanding of the properties of native human nAChRs, α7 in particular.
源自人类诱导多能干细胞（iPSC）的神经元是用于表征神经元受体和离子通道的潜在有价值工具。先前对iPSC衍生神经元细胞的研究报道了多种受体和离子通道的功能特性，包括谷氨酸受体、γ-氨基丁酸（GABA）受体和几种电压门控离子通道。在本研究中，我们检测了人类iPSC衍生神经元中烟碱型乙酰胆碱受体（nAChR）的表达和功能特性。基因表达分析表明存在编码几种nAChR亚基的转录本，其中α3-α7、β1、β2和β4亚基（由CHRNA3-CHRNA7、CHRNB1、CHRNB2和CHRNB4基因编码）的表达水平最高。此外，还检测到由部分重复基因CHRFAM7A编码的截短型dupα7亚基转录本的类似高转录水平，该基因与精神分裂症等精神疾病有关。这些nAChR的功能特性已通过钙荧光和膜片钳记录进行了检测。获得的数据表明，这些细胞中表达的大多数功能性nAChR具有α7受体典型的药理学特性。在α7选择性正变构调节剂（PAM）PNU-120596存在下，选择性α7激动剂（化合物B）诱导了大的反应，这些反应被α7选择性拮抗剂甲基lycaconitine（MLA）阻断。此外，一小部分神经元表达具有异聚体（不含α7）nAChR亚型典型特性的nAChR。因此，这些细胞是推进我们对天然人类nAChR特性理解的重要工具，尤其是α7。
