Figure 1. Isoforms, antisera, and expression of cadherin 23 isoforms. A: This panel illustrates schematically (not drawn to scale) four classes of Cdh23 transcripts (GeneID 22295), CDH23 protein isoforms, and the locations of TaqMan probes. Gene and protein variants were designated according to Jax. Transcripts that include exon 68 are designated with an “a,” and transcripts lacking exon 68 are designated “b.” Protein variants V1, V2, and V3 are encoded by transcripts v1, v2, v3, respectively with (a) or without (b) exon 68. B: Bar graphs show data from real-time PCR assays of Cdh23 transcripts in wild-type and waltzer Cdh23^v-6J mouse inner ear (black bars) and retina (white bars) during development. The relative expression levels of Cdh23 transcripts detected with assays 47–48, 47a-48 and 44–48 (A) are shown in ∆∆C_t values. Expression levels of Cdh23 transcripts are reported as ∆∆C_t values, in which the RNA level is: 1) expressed in terms of the cycle at which exponentially accumulating cDNA product can be detected above background in an RT_PCR reaction (the threshold cycle or “C_t”); 2) normalized to the C_t of Gapdh as an endogenous control (the “ΔC_t”); and then 3) reported relative to an arbitrarily chosen calibrator, in this case E16.5 inner ear expression level using probe 44–48 (“∆∆C_t”). Abbreviations: extracellular (EC), transmembrane (TM), cytoplasmic (Cyto), PDZ binding motif (PBM).