Two types of ATPases from the Pacific white shrimp, Litopenaeus vannamei in response to environmental stress

V-H ATPase and NaK ATPase are important classes of ATP-driven proton pumps that are present in the intracellular and plasma membranes of eukaryotic cells and play diverse roles in both normal and abnormal cellular processes. Among the subunits of the V-H ATPase complex, subunit a is a transmembrane glycoprotein that plays crucial roles in metabolism, growth, survival and cellular immunity. NaK ATPase subunit beta is thought to participate in the proper folding and movement of the NaK ATPase enzyme and may also aid cation transport. In this study, we analyzed the functions of V-H ATPase subunit a and NaK ATPase subunit beta from the Pacific white shrimp, Litopenaeus vannamei. Full-length cDNAs of the genes corresponding to V-H ATPase subunit a and NaK ATPase subunit beta were obtained, which were 2654 and 2055 bp long, with open reading frames encoding 830 and 313 amino acids, respectively. RT-PCR analysis indicated that mRNA transcripts were strongly (but differentially) expressed in the gills and hepatopancreas, and at lower levels in other shrimp tissues. In this study, for the first time, the gene expression of V-H ATPase subunit a and NaK ATPase beta of white shrimp Litopenaeus vannamei were analysed by quantitative real-time PCR after exposure to five kinds of environmental stresses (bacteria, pH, Cd, salinity and low temperature). The results demonstrate that both of the two genes are sensitive and involved in all different stress responses and are more sensitive to salinity than other stresses. And they may have relationship with the anti-stress mechanism induced by environment stress in shrimp.