An induced pluripotent stem cell line carrying a silencing-resistant calcium reporter allele.

Calcium indicators are sensitive tools to image neural activity. However, their use in human induced pluripotent stem cells (iPSC)-derived neurons is limited by silencing of the transgene. We generated the iPSC line MSE2336A carrying heterozygous insertion in the safe-harbor locus AAVS1 of the ultrasensitive protein calcium sensor (GCaMP6) under the control of CAG promoter and UCOE to maintain robust transgene expression in differentiated cells. The iPSC exhibited normal cell morphology, expression of pluripotency markers, genome integrity, and the ability to differentiate into the three primary germ layers. This line provides a powerful model to study activity in human neurons.