Submitted to: Journal of Proteomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/31/2009
Publication Date: 2/10/2010
Publication URL: http://handle.nal.usda.gov/10113/55643
Citation: Salem, M., Kenney, B.P., Rexroad Iii, C.E., Yao, J. 2010. Proteomic signature of muscle atrophy in rainbow trout. Journal of Proteomics. 73(4):778-789. Interpretive Summary: Constituting 60-65% of fish weight, muscle is the edible part of the fish that is a highly desirable source of protein and trace nutrients required for human health. Muscle deterioration arises as a physiological response to elevated energetic demands of fish sexual maturation and spawning. Comparing the muscle characteristics of fish which are spawning to sterile fish provides a unique model to identify potential biochemical markers for enhanced muscle growth and fillet quality. To this end we identified 381 muscle proteins, 146 of which were observed to be significantly different in atrophying tissues. These results were similar to previously conducted gene expression experiments, which validated the identification of biochemical processes involved in muscle deterioration. These proteins serve as candidates for genetic improvement of muscle growth and quality in rainbow trout.
Technical Abstract: Muscle deterioration arises as a physiological response to elevated energetic demands of fish sexual maturation and spawning. Previously, we used this model to characterize the transcriptomic mechanisms associated with muscle degradation in fish and identified potential biological markers of muscle growth and quality. However, transcriptional measurements do not necessarily reflect the amount of change in active mature proteins. To characterize the global proteomic profile in degenerating muscle of rainbow trout in relation to the female reproductive cycle we used a LC/MS-based label-free protein quantification method. A total of 381 proteins were identified in tissue lysates. This approach identified 146 significantly changed proteins in atrophying muscles (FDR <5%). Proteins were clustered according to their gene ontology identifiers. Muscle atrophy was associated with decreased abundance in proteins of anaerobic respiration, protein biosynthesis, monooxygenases, follistatins, myogenin in addition to receptors of growth hormone, interleukin-1 and estrogen. In contrast, atrophying muscle showed increased abundance in proteins of MAPK/ERK kinase, glutamine synthetase in addition to transcription factors Stat3, JunB, Id2, and NFkappaB inhibitor. These changes are discussed in light of the mammalian muscle atrophy paradigm and suggested fish-specific mechanisms of muscle degradation. These data will help identify genes associated with muscle degeneration and flesh quality in rainbow trout with ultimate goal of identifying genetic markers for muscle growth and fillet quality.