Animal Science Papers and Reports

Polymorphism in CTSB exon 7 as associated with activity of the lysosomal proteases in longissimus dorsi muscle of growing Friesian bulls

Edyta Juszczuk-Kubiak1,**, Stanis³aw Rosochacki1,2, Krzysztof S³oniewski1, Jaros³aw Po³oszynowicz1, Krystyna Wiciٌska1

Abstarc :

Proteolysis regulation is one of the key factors in meat processing. Cathepsins are a group of
acid lysosomal proteases involved in post-mortem muscle proteolysis and have one of the utmost
importance for meat products quality. The aim of the study was to compare activities of lysosomal
proteases in skeletal muscle (longissimus dorsi – LD) of growing Friesian bulls of different cathepsin
B (CTSB) loci genotypes. Samples from the same region of XIII vertebra of LD were obtained
post-slaughter from 157 Friesian bulls aged about 11 months. In relation to proteolytic activity of
the LD muscle significant differences were identified between bulls representing different CTSB
genotypes. In samples from bulls of CC/CTSB genotype higher activities were found for acid
autolytic activity (AAA, P<0.01), pepstatin-insensitive acid autolytic activity (PIAAA, P<0.01) and
leupeptin-insensitive acid autolytic activity (LIAAA, P<0.05) than in samples from TT/CTSB bulls.
The protein content of LD was higher by 5.0% in muscle samples from bulls of TT than of CT
genotype (P<0.05).

Key Word :
cathepsin B gene / cattle / cysteine and aspartic proteases / gene polymorphism / meat quality / proteases / proteolysis

Volume 25, Number 4, - 2007