Figure S6.

iMb2- and iChr2-Mosaic Recombination Frequencies and Signals, Related to Figure 7

(A) Diagrams showing the genetic distances between the LoxP sites in the DNA constructs used to produce the different ifg2Mosaic mice. Genetic distance is not the only factor that influences the relative ratios of recombination. The frequencies (%) indicated above the FACS plots were obtained in ES cells transfected with Cre-expressing plasmids and analysed by FACS, and later confirmed also by immunostaining. The frequencies below were obtained by confocal microscopy of ECs from ifg2Mosaic Cdh5-CreERT2+ mice, pulsed once with tamoxifen. The differences observed in the recombination ratios are caused by the higher levels of Cre activity obtained in ES cells than in ECs expressing CreERT2 and pulsed only once with tamoxifen.

(B) Confocal micrograph showing the 4 signals detected after immunostaining with the indicated antibodies, of the postnatal mouse retina of Dual ifg2Mosaic mice, carrying the Cdh5-CreERT2 allele, and pulsed once with tamoxifen.

(C) Endogenous fluorescence detection in endothelial cells of the same mice after retina tissue fixation, and labeling with conjugated IsolectinB4-647. A total of 7 fluorescent signals (6 endogenous and 1 immunolabeled), excited with the indicated laser lines, could be detected with high resolution and in a large acquisition field. Magnified boxed areas and two-letter codes show selected double-recombined cell clones and the observed combination of FPs A to F, at higher magnification. Pictures further below show the different signals separately.