Fig. 5.

Lentivirus-based genomic integration of the SARE reporter. (A) Design of lentiviral vectors. Top, the SARE reporter vector encodes an inducible reporter GFP (d2EGFP) under the control of SARE-ArcMin and a constitutively expressed infection marker RFP (TurboFP635) under the control of a pgk promoter. Bottom, a control vector lacking SARE. (B) Hippocampal neurons infected with the SARE reporter lentivirus were stimulated with BDNF for 6 h at 14 days postinfection. (Scale bar, 50 μm.) (C) GFP live-cell imaging of SARE-virus-infected neurons stimulated with high-frequency electrical pulses. Hippocampal neurons infected with the SARE reporter lentivirus were stimulated with field electrical pulses at time 0 h (triangle, 100 pulses at 100 Hz, 9 times), and GFP fluorescence was monitored. Gray lines, traces of individual neurons. Filled squares, the average trace of all neurons examined (n = 59). Open circles, the average trace of highly reactive neurons (top 10% of all neurons sorted by the F/F₀ value at the time of 8 h, n = 6). (D) No GFP fluorescence changes were observed in control-virus-infected neurons. Filled squares, the average trace of all neurons examined (n = 18).