Fig. 3

One-step generation of conditional knockout animals (F0) by CLICK. a Schematic representation of applying CLICK in oocytes for in vitro fertilization (IVF) with Cre-driver mice, Emx1-cre, resulting in brain-specific recombination at the targeted floxed alleles. b PCR analysis of representative delivered mouse pups by microinjection (#1–8) or electroporation (#9–15) showing different types of mutations, indels, LD, and floxed alleles (black arrow) at the targeted Serpina3n locus. The primer sets (‘small’ in Additional file 2: Figure S2) were used for PCR and sequence analysis. c Genotyping in several tissues: cerebrum (Cr), cerebellum (Cl), heart (H), liver (L), spleen (S), and testis (Ts), indicating recombination (red arrow) by brain-specific Cre expression in #14 mouse carrying heterozygous floxed with LD alleles. M: 100 bp DNA ladder marker. d Time-schedule comparisons of targeting methods using ES cells by CRISPR in B6 oocytes, and CLICK in Cre oocytes. CLICK saves about 6 months of crossing and reduces breeding costs during the study period (Additional file 13: Figure S13)