Identification of a predominant subtype and alternative transcriptional variants of L-type calcium channels expressed in SMC.

<p>(A) Expression levels of L-type calcium channel subtypes in SMC of jejunum and colon. (B) Expression levels of <i>Cacna1c</i> variants in SMC and tissue of jejunum and colon. (C) A genomic map of <i>Cacna1c</i> variants. Five variable regions (V1-5) are indicated. Exons are numbered 1–48. (D) Magnified view of variable regions showing alternatively started or spliced exons (indicated as exon numbers). Seven exons containing alternative transcriptional start sequence are shown by a star (*). Long (L) and short (S) exons that are differentially started or spliced are indicated.