Figure 3:

Whrn genomic DNA and mRNA variants in wild-type and Whrn mutant mice. (A) FL-, N-, and C-terminal whirlin mRNA variants found in the wild-type mice. For simplicity, only one representative N-whirlin mRNA variant is shown, although several N-whirlin mRNA variants have been reported (Belyantseva et al., 2005; Ebrahim et al., 2016; Mathur et al., 2015b; Wright et al., 2012). In addition, the C-whirlin variants starting from exon 1 are not shown. (B) A deletion from exon 6 to exon 10 (red box) truncates both FL-whirlin mRNA and C-whirlin mRNA variants in Whrn^wi mice. A vertical yellow bar indicates a premature stop in truncated Whrn^wi mRNA fragments. N-whirlin mRNA variants were not found in our study, although they were found in the Whrn^wi inner ear by Ebrahim et al. (Ebrahim et al., 2016; Mathur et al., 2015b; Mathur et al., 2015c). (C) Only a C-terminal whirlin variant is present in Whrn^neo mice, which has a Neo^r cassette (orange box) in the 5′ region of exon 1. (D) A targeting cassette (light blue box) in intron 3 of Whrn^tm1a genomic DNA (gDNA) disrupts the FL-whirlin variant. However, it is expected that the C-terminal whirlin mRNA variant remains unaffected. L, loxP site. (E) Exon 4 and a part of the targeting cassette (light blue box) in Whrn^tm1a gDNA are deleted in Whrn^tm1b mice, which disrupts the FL-whirlin variant. The C-terminal whirlin mRNA variant is expected to be unaffected. (F) Whrn^wi+BAC mice are expected to express C-terminal whirlin mRNA variant from the transgenic BAC DNA, in addition to the variants expressed in Whrn^wi mice. Brown and light grey in the Whrn gDNA and BAC DNA denote the exons and introns, respectively, with exon numbers in Arabic numerals. White color denotes 5′ and 3′-untranslated regions, and green color denotes the coding sequence region of whirlin mRNA variants.