Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/12/1999
Publication Date: N/A
Interpretive Summary: Calpastatin is a specific, endogenous inhibitor of the calcium- dependent neutral proteases (calpains) that plays a regulatory role in muscle proteolysis and post-mortem meat tenderization. Calpastatin has previously been mapped to bovine chromosome 7 using an RFLP requiring Southern blotting of genomic DNA. We characterized a (CA)n microsatellite in the promoter region of the bovine calpastatin gene and mapped this marker to the same locus as the RFLP. This PCR-based polymorphism identified 9 alleles, with 71% heterozygosity in our mapping population. The addition of this highly informative microsatellite marker for calpastatin should be useful to determine if calpastatin is linked to QTL involved in meat quality and muscle growth.
Technical Abstract: Primers were designed from a published sequence of the bovine calpastatin 5'-flanking region surrounding a CA repeat to amplify a product from genomic DNA of approximately 246 bp that was used for sequencing. A polymorphic 126-154 bp amplicon was produced with for microsatellite analysis. The polymorphism was a (CA)n repeat that identified 9 alleles in the MARC mapping population with fragment lengths of 126, 132, 136, 142, 146, 148, 150, 152, and 154 bp. Heterozygosity in this population was 71%. Codominant Mendelian inheritance of alleles was observed in the MARC reference pedigree. Frequency of alleles of the parents in the MARC reference pedigree was 0.013, 0.31, 0.013, 0.052, 0.49, 0.026, 0.065, 0.013, and 0.013 for fragments of 126, 132, 136, 142, 146, 148, 150, 152, and 154 bp, respectively. There were 218 informative meiosis for the bovine calpastatin microsatellite, with two-point LOD scores ranging from 3.11-43.93. Calpastatin has previously been mapped to bovine chromosome 7, relative position 117.8 using an RFLP. The microsatellite marker reported here maps to the same chromosomal location as the RFLP marker.