Down-regulation of KChIP2 in mXinα-deficient mouse hearts. (A) Total RNAs (10 μg each lane) prepared from wild-type (+/+, lane 1), heterozygous (+/−, lane 2) and homozygous (−/−, lane 3) mXinα mouse hearts were blotted and hybridized with a mixture of 32P-labeled mXinα cDNA and KChIP2 cDNA probes. For the RNA loading control, the same blot was further hybridized with GAPDH cDNA probe. (B) A longer exposure of the same Northern blot was shown to reveal the KChIP2 message band in mXinα-deficient hearts.