Research Paper Volume 12, Issue 9 pp 8202—8220

A cellular surveillance and defense system that delays aging phenotypes in C. elegans

Figure 2. ZIP-2 activity increases in aging. (A) Relative expression levels of irg-1 in wild-type (N2) and zip-2(ok3730) mutant worms at day 1 and day 8 of adulthood. (B) Relative expression levels of irg-2 in wild-type and zip-2(ok3730) mutant worms at day 1 and day 8 of adulthood. (C) (I) Relative expression level of zip-2 in wild-type at day 1 and day 8 of adulthood. (II) Representative images of zip-2p::GFP expression pattern at day 1 or day 8 of adulthood in wild-type strains. Scale bar: 100 μm. All relative expression levels were assessed by qRT-PCR, normalized to act-3. Error bars represent SEM by three independent experiments. (D) (I) irg-1p::GFP expression pattern at day 1 of adulthood in L4440 RNAi worms (a). irg-1p::GFP expression pattern at day 8 of adulthood in L4440 RNAi worms (b) or zip-2 RNAi worms (c). Scale bar: 100 μm. (II and III) Relative GFP intensity in intestine. GFP intensity of individual worms was normalized to the minimum GFP intensity value among all GFP intensity values. Shown are the relative irg-1p::GFP intensities in L4440 RNAi worms (n=19) at day 1 of adulthood, in L4440 RNAi (n=19) and zip-2 RNAi (n=20) worms at day 8 of adulthood. The n value represents total number of tested worms by two independent experiments. Shapiro-Wilk normality test was used to assess normal distribution of the samples. Significance was determined using a two-tailed, unpaired t-test. * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001.