Khattak Shahryar, Brimble Elise, Zhang Wenbo, Zaslavsky Kirill, Strong Emma, Ross P Joel, Hendry Jason, Mital Seema, Salter Michael W, Osborne Lucy R, Ellis James
Program in Developmental and Stem Cell Biology, Hospital for Sick Children, Toronto, ON, Canada.
Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.
Mol Brain. 2015 Nov 24;8(1):77. doi: 10.1186/s13041-015-0168-0.
Williams-Beuren Syndrome (WBS) is caused by the microdeletion of approximately 25 genes on chromosome 7q11.23, and is characterized by a spectrum of cognitive and behavioural features.
We generated cortical neurons from a WBS individual and unaffected (WT) control by directed differentiation of induced pluripotent stem cells (iPSCs). Single cell mRNA analyses and immunostaining demonstrated very efficient production of differentiated cells expressing markers of mature neurons of mixed subtypes and from multiple cortical layers. We found that there was a profound alteration in action potentials, with significantly prolonged WBS repolarization times and a WBS deficit in voltage-activated K(+) currents. Miniature excitatory synaptic currents were normal, indicating that unitary excitatory synaptic transmission was not altered. Gene expression profiling identified 136 negatively enriched gene sets in WBS compared to WT neurons including gene sets involved in neurotransmitter receptor activity, synaptic assembly, and potassium channel complexes.
Our findings provide insight into gene dysregulation and electrophysiological defects in WBS patient neurons.
威廉斯-贝伦综合征(WBS)由7号染色体长臂11.23区域约25个基因的微缺失引起,其特征为一系列认知和行为特征。
我们通过诱导多能干细胞(iPSC)的定向分化,从一名WBS个体和未受影响的(野生型)对照中生成了皮质神经元。单细胞mRNA分析和免疫染色表明,能够非常高效地产生表达混合亚型成熟神经元标记物且来自多个皮质层的分化细胞。我们发现动作电位存在显著改变,WBS复极化时间明显延长,且电压激活的钾离子电流存在WBS缺陷。微小兴奋性突触电流正常,表明单一兴奋性突触传递未改变。基因表达谱分析确定,与野生型神经元相比,WBS中有136个负富集基因集,包括参与神经递质受体活性、突触组装和钾通道复合物的基因集。
我们的研究结果为深入了解WBS患者神经元中的基因失调和电生理缺陷提供了依据。