Genomic Structure and Expression of the Porcine ACTC1 Gene

A partial cDNA (similar to 1200 bp) of the porcine ACTC1 gene was identified in the subtracted foetal hind limb muscle cDNA library (44 days of gestation; using m. biceps femoris cDNA as the driver). Using specific polymerase chain reaction (PCR) primers, a bacterial artificial chromosome (BAC) clone containing the genomic ACTC1 gene was identified and the gene was sequenced. Specific PCR primers designed from the BAC and cDNA sequences were used for amplification and comparative sequencing of ACTC1 of Pietrain and Meishan pigs. The gene is approximately 5.4 kb in length, is composed of 7 exons, and has a coding sequence containing 1134 bp. The gene was mapped using the INRA-Minnesota porcine radiation hybrid (IMpRH) panel to chromosome 1, with SW65 as the closest marker (41 cR; LOD = 7.73). Differences were observed in tissue-specific expression of ACTC1 that was studied by transcription profiling in 28 porcine tissues. Developmental differences in muscle and heart were analysed by real-time quantitative PCR (RT-qPCR). Two single nucleotide polymorphisms (SNPs) were found in intron 1. One adequately informative SNP (FM212567.1:g.901C>G) was genotyped by PCR-restriction fragment length polymorphism, and allele frequencies in eight pig breeds were calculated.