Tg(CAG-GCaMP2)2Mik

This 3.7 kbp transgene has a loxP site, the CMV-IE enhancer/chicken beta-actin/rabbit beta-globin hybrid promoter (from pCAGGS), the GCaMP2 sequence (described below), a polyadenylation signal and a second loxP site. Founder line 2 was identified with high sensor expression. The genetically encoded calcium indicator GCaMP2 is a calcium-sensing molecule composed of a 35 aa polyHis plasmid leader sequence (RSET; essential for thermal stability), a 13 residue peptide of chicken smooth muscle myosin light chain kinase (M13), a circularly permutated EGFP (cpEGFP; aa 149-238 followed by aa 1-144 [with mutations listed below]), and a rat calmodulin DNA fragment (CaM; aa 2-148). The cpEGFP mutations result in increased brightness (D180Y and V93I), thermal stability (V163A and S175G) and GFP dimerization prevention (A206K). (J:101977)