Genomic structure of the 5 ' end of the porcine ryanodine receptor 3 gene (RYR3)

Ryanodine receptor 3 is a calcium channel located in the membrane of the endoplasmic reticulum. We isolated eight overlapping PAC clones from the porcine ryanodine receptor 3 gene (RYR3) and determined the DNA sequences of the first and second exon together with 5.8 kb of 5' flanking region and 10.3 kb of intron sequences. By comparing the porcine genomic sequence to the human RYR3 cDNA sequence the porcine transcription start site could be mapped to a GC-rich region. Physical mapping of the isolated PAC clones revealed that the complete porcine RYR3 gene spans more than 200 kb of genomic DNA.