Quantification and modeling of signalling dynamics in single hematopoietic stem and progenitor cells

Abstract

Signalling pathways influence fate decisions of hematopoietic cells. However, quantifying signalling dynamics over time and linking these to future fate decisions of the same individual cells have been technically infeasible. Here, we establish continuous single-cell time-lapse imaging to quantify the activity of various signalling pathways over time in living hematopoietic stem and progenitor cells (HSPCs). Live signalling biosensors reporting the activity of the ERK, PI3K/AKT, STAT3, WNT and NOTCH signalling pathways are combined to generate a transgenic mouse line simultaneously displaying their activity. Isolating known single cells after live observation allows to link signalling dynamics to live functional assays or to destructive high-dimensional RNA or protein quantification. We expect to identify novel HSPC sub-populations with specific signalling responses, and a better understanding of the relevance of signalling pathways in controlling transcriptional programs and HSPC fates, of molecular HSC control in general.