The cardiac pacemaker-specific channel Hcn4 is a direct transcriptional target of MEF2.

Aims: Hcn4, which encodes the hyperpolarization-activated, cyclic nucleotide-sensitive channel (I(h)), is a well-established marker of the cardiac sino-atrial node. We aimed to identify cis-elements in the genomic locus of the Hcn4 gene that regulate the transcription of Hcn4.

Methods And Results: We screened evolutionarily conserved non-coding sequences (CNSs) that are often involved in the regulation of gene expression.