Fig 1: Multiple gRNAs facilitate the transcription of the endogenous mouse Serpina1(a-e) genes in vivo. (A) Relative position of the 6 individual gRNAs (black bars) per Serpina1 (a-e) paralogue, aiming to upregulate transcription, are shown. The transcription start site (TSS) in the promoter region is shown as a black arrow. The numbers indicate the base pair distance to the TSS. The position where individual gRNAs bind to the genome is displayed relative to the TSS of the respective Serpina1 transcript (Serpina1a-203 (ENSMUST00000124717.2), Serpina1b-201 (ENSMUST00000095450.11), Serpina1c-201 (ENSMUST00000074051.6), Serpina1e-202 (ENSMUST00000122229.8), Serpina1d-201 (ENSMUST00000078869.6)). (B) Outline of the in vivo experiment. Rosa26-LSL-dCas9-VPR mice were iv injected with AAV8 containing LP1-Cre (AAV8-Cre) alone or in parallel with a set of 5 different AAV8s, carrying gRNAs against 5 Serpina1 paralogues, at the amount of 1 × 1011 VG/mouse. 21 days later mice were sacrificed, and tissues were collected for analysis. (C,D) Serpina1(a-e) mRNA and protein expression in liver tissue dissected from Rosa26-LSL-dCas9-VPR mice, treated with only AAV8-Cre or with a set of six different viruses, AAV8-Cre, AAV8-gSerpina1a, AAV8-gSerpina1b, AAV8-gSerpina1c, AAV8-gSerpina1d and AAV8-gSerpina1e. Mean values are shown as a relative quantification, with corresponding expression level of AAV-Cre treated control group as a reference (n = 9–10). (E) AAT protein levels in mouse plasma from Rosa26-LSL-dCas9-VPR mice. Means and standard deviations are shown, n = 10.