Tissue-specific expression of splice variants of the mouse voltage-gated calcium channel α2/δ subunit

AbstractFive different splice variants of mouse α2/δ subunit isoforms (α2/a-e), which arose from various combinations of three alternatively spliced regions, were cloned with a combination of cDNA library screening and RT-PCR. Expression patterns and relative abundance of the various isoforms in mouse tissues were determined with an RNAse protection assay. Skeletal muscle and brain expressed single isoforms, α2a and α2b, respectively; however, the cardiovascular system expressed all five isoforms. Heart expressed mainly isoforms α2c and α2d while, in contrast to other species, aorta expressed predominantly α2a, the ‘skeletal muscle’ isoform. Smooth muscle-containing tissues expressed α2d and α2e. Thus, α2/δ isoforms are restricted in their tissue expression, suggesting an important functional role for the differentially spliced variants