Figure 1.

Age affects hepatic response to ASNase. ASNase exposure stunts body growth (A) and reduces relative liver mass (B) in juveniles but not in adults following 1 week of daily intraperitoneal injections as compared with control groups that were injected with vehicle (PBS). The box plots show median values, top and bottom hinges correspond to the first and third quartiles (the 25th and 75th percentiles), and the whiskers extend to the smallest and the largest value within 1.5 distance of the interquartile range. *, p < 0.05 by Wilcoxon rank-sum test. C, schematic diagram of the experimental setup to analyze hepatic transcriptomes of the mice; n indicates group number. D, principal component analysis clusters juvenile mice separately from adult mice regardless of treatment. E, Venn diagram shows numbers of commonly and uniquely altered transcript abundances in the murine hepatic transcriptomes discovered in the two comparison sessions: (i) juveniles (blue set) versus combined 8- and 16-week-old adult group (red set) and (ii) juveniles (green set) versus 16-week-old mice (yellow set). Boldface underlined numbers of the colored Venn diagram were further filtered using the 2-fold change cutoff in gene expression induced by ASNase, resulting in 28 common, 80 juvenile-specific, and 34 adult-specific elements for further analysis of functional association.