Proteomics reveals the preliminary physiological states of the spotted seal (Phoca largha) pups

Abstract

AbstractSpotted seal (Phoca largha) is a critically endangered pinniped in China and South Korea. The conventional method to protect and maintain theP. larghapopulation is to keep them captive in artificially controlled environments. However, little is known about the physiological differences between wild and captiveP. largha. To generate a preliminary protein expression profile forP. largha, whole blood from wild and captive pups were subjected to a label-free comparative proteomic analysis. According to the results, 972 proteins were identified and predicted to perform functions related to various metabolic, immune, and cellular processes. Among the identified proteins, the expression level of 51 were significantly different between wild and captiveP. largepups. These differentially expressed proteins were enriched in a wide range of cellular functions, including cytoskeleton, phagocytosis, proteolysis, the regulation of gene expression, and carbohydrate metabolism. The abundances of proteins involved in phagocytosis and ubiquitin-mediated proteolysis were significantly higher in the whole blood of wildP. larghapups than in captive individuals. In addition, heat shock protein 90-beta, were determined as the key protein associated with the differences in the wild and captiveP. larghapups due to the most interactions of it with various differentially expressed proteins. Moreover, wildP. larghapups could be more nutritionally stressed and have more powerful immune capacities than captive pups. This study provides the first data on the protein composition ofP. larghaand provides useful information on the physiological characteristics for research in this species.