Catalytic subunits atp alpha and atp beta from the Pacific white shrimp Litopenaeus vannamei F sub(O)F sub(1) ATP-synthase complex: cDNA sequences, phylogenies, and mRNA quantification during hypoxia

In the mitochondrial F sub(O)F sub(1) ATP-synthase/ATPase complex, subunits alpha and beta are part of the extrinsic portion that catalyses ATP synthesis. Since there are no reports about genes and proteins from these subunits in crustaceans, we analyzed the cDNA sequences of both subunits in the whiteleg shrimp Litopenaeus vannamei and their phylogenetic relationships. We also investigated the effect of hypoxia on shrimp by measuring changes in the mRNA amounts of atp alpha and atp beta . Our results confirmed highly conserved regions for both subunits and underlined unique features among others. The ATP beta deduced protein of shrimp was less conserved in size and sequence than ATP alpha . The relative mRNA amounts of atp alpha and atp beta changed in shrimp pleopods; hypoxia at 1.5mg/L caused an increase in atp beta transcripts and a subsequent decrease when shrimp were re-oxygenated. Results confirm that changes in the mRNAs of the ATP-synthase subunits are part of the mechanisms allowing shrimp to deal with the metabolic adjustment displayed to tolerate hypoxia.