Figure 1. B6-kl/kl mice maintain an overall lower body weight than C57BL/6 as they age. (A) A graphical representation of the kl gene. Black arrows indicate the primer sets used to amplify the secreted and membrane forms by quantitative PCR. (B) Secreted kl mRNA and (C) membrane kl mRNA expression in kidney normalized to gapdh at 1-3 months, 4-7 months, and 8+ months of age (n=2 per group). Bars represent standard error mean. Statistical significance determined by 2way ANOVA and Tukey’s multiple comparison test: ** p ≤ 0.01, *** p ≤ 0.001, and *** p ≤ 0.0001. Weights of C57BL/6 and B6-kl/kl (D) male and (E) female mice at 1-3 months, 4-7 months, and 8+ months of age. For male mice C57BL/6 1-3 months n=34, 4-7 months n=8, and 8+ months n=11 and B6-kl/kl 1-3 months n=21, 4-7 months n=14, and 8+ months n=11. For female mice C57BL/6 1-3 months n=38, 4-7 months n=8, and 8+ months n=13 and B6-kl/kl 1-3months n=17, 4-7 months n=19, and 8+ months n=19. Statistical significance determined by multiple t tests: * p ≤ 0.05, ** p ≤ 0.001, and **** p ≤ 0.0001.