Download Molecular characterization of calpastatins from Rainbow trout:

Submitted to Aquaculture America, 2005.
Molecular characterization of calpastatins from Rainbow trout:
Their role in muscle growth and texture development
MOHAMED SALEM1, 4, JIANBO YAO1, CAIRD E. REXROAD2,
BRETT KENNEY1, KENNETH SEMMENS1, JOHN KILLEFER3,
AND JOGINDER NATH4
1
Division of Animal and Veterinary Sciences, West Virginia University,
Morgantown, WV 26506-6108
2
National Center for Cool and Cold Water Aquaculture, Kearneysville, WV 25430
3
Department of Animal Sciences, University of Illinois at Urbana-Champaign,
Urbana, IL 61801
4
Genetics and Developmental Biology Program, West Virginia University,
Morgantown, WV 26506-6108
ABSTRACT
Calpastatin (CAST) is a specific inhibitor of the calpain proteases that play a
significant role in the steady state muscle protein turnover during animal growth and
impacts the postmortem whole-muscle food texture. We identify two CAST cDNAs
from the rainbow trout: long isoform (CAST-L) and short isoform (CAST-S) with
77% amino acid identity. Translation of CAST-L cDNA (2600 bp) gave 497 amino
acids with expected MW of 52.5 KDa. CAST-S showed 2 splice variants; variant 1
(2132 bp) gave 296 amino acids with expected MW of 31.5; variant 2 (2246 bp) has a
premature stop signal gave 154 amino acids with expected MW of 16.3. The rainbow
trout CASTs were used to retrieve a cDNA homologous sequence from zebra fish.
The rainbow trout CAST-L showed 19% and 44%, amino acid sequence identity with
Submitted to Aquaculture America, 2005.
mouse and zebra fish CASTs, respectively. CAST-S variant 2 showed 25% and 51%
identity, respectively. Expression of CAST messenger RNA was measured by the real
time RT-PCR in 3 rainbow trout strains different in their growth rates and higher filet
firmness. Fish were fed either high or low energy diets. CAST-L and CAST-S
expressions were higher in fish strains with faster growth rates and higher filet
firmness. Energy content of the feed diet did not lead to a significant effect on CAST
expression. These results point to the potential use of CAST gene as a biogenetic tool
to enhance fish muscle growth and texture quality.