Generation of Fga²⁷⁰ mice that express low levels of fibrinogen with a truncated form of Aα chain after residue 270. (A) Summary of the nucleic acid substitutions introduced by Crispr-Cas9 gene editing and resulting amino acid changes for the mutated fibrinogen Aα-chain gene of the Fga²⁷⁰ mice. Asterisks highlight positions of the nucleotide substitutions. (B) Representative PCR analysis to establish animal genotypes of Fga^WT/WT, Fga^WT/270, and Fga^270/270 mice. (C) ELISA measurement of plasma fibrinogen levels from Fga^WT/WT, Fga^WT/270, and Fga^270/270 mice from 2 independent lines (n = 3-4 per genotype). One-way ANOVA was used to determine statistical significance. (D) Western blot analysis of plasma (reducing conditions) from Fga^WT/WT, Fga^WT/270, Fga^270/270, and Fga^−/− mice using antibodies directed against the Aα chain of fibrinogen. Analysis of hepatic mRNA levels by quantitative reverse transcriptase PCR for (E) Fga, (F) Fgb, and (G) Fgg in Fga^−/− mice and 2 independent lines of Fga²⁷⁰ mice (n = 4 per genotype). One-way ANOVA test was used to determine statistical significance. Analysis of fibrinogen (H) Fga and (I) Fgb gene expression from primary mouse hepatocytes isolated from Fga^WT/WT, Fga^WT/270, and Fga^270/270 mice treated with or without 100 μM cycloheximide (CHX) for 3 hours (n = 3-4 per treatment group). Two-tailed Student t test was used to determine statistical significance. *P < .05, **P < .01, ***P < .001, ****P < .0001. ns, no statistical significance.