Comparative proteomics for identification of reproductionrelated proteins in testes of the giant tiger shrimp penaeus monodon

Abstract

Testicular proteome of wild and domesticated 14-and 18-month-old broodstock of the giant tiger shrimp Penaeus monodon was examined. Among 344 differentially expressed proteins identified, 11 proteins (e.g. p97/VCP-binding protein p135, lipoxygenase homology domains 1 and dipeptidyl-peptidase, accounting for 4.95% of proteins with known functions) were found in wild broodstock but not in domesticated broodstock while 152 (68.47%) proteins were commonly found in all groups of samples. Reproduction-related proteins such as vasa-like protein, Wee1-like protein kinase, serine/threonine protein kinase, mitogen activated protein kinase kinase 2, GTP-binding protein alpha subunit, seven membrane helix receptor, nuclear receptor subfamily 3, were identified. To examine a possible role of the signal transduction system in development of testes of P. monodon, the expression level of testicular serine/arginine rich-protein kinase 3 (PmSrpk3) mRNA of domesticated juveniles and broodstock was examined and it was significantly lower than that of wild P. monodon broodstock (P<0.05). PmSrpk3 expression was significantly induced by serotonin (P<0.05) but not progesterone (P>0.05) injection. The expression profiles of PmSrpk3 indicated reduced reproductive maturation of domesticated male P. monodon and exogenous administration of serotonin may be applied for promoting the testicular development of captive P. monodon.