Fig. 4.

Massive reduction in class I gene expression in ∆J. a A targeted deletion of the J element using the CRISPR-Cas9 system. b PCR genotyping of wild-type ( + / + ), heterozygous ( + /−), and homozygous (−/−) mice using primers covering the J element. c, d Microarray analysis of OR gene expression in ΔJ mice. c The log2-fold change (FC) values for class I OR genes are shown in the class I OR cluster position. A fold change criterion of 1.3 (decrease or increase) was used. Differentially expressed class I OR genes (p < 0.05) are represented by filled circles (n = 6). Among 129 tested intact class I OR genes within the class I cluster, the expression of 75 class I OR genes is decreased and that of one gene is increased. Pearson correlation coefficient r = 0.42, p = 9.7 × 10⁻⁷. d The log2 FC values for all tested intact OR genes arranged according to their relative positions along the chromosome (class I, blue; class II, magenta; n = 6). e Single-color ISH analysis for five class I OR genes, one atypical class I OR gene, and two dorsal class II OR genes in ΔJ and wild-type mice. The scale bar is 50 μm. f Correlation between log2 FC values detected by microarray (horizontal axis) and ISH (vertical axis) for twelve class I, two atypical class I, and four class II OR genes. n ≥ 3. Pearson correlation coefficient r = 0.87, p = 3.6 × 10⁻⁶