Abstract:Adenine nucleotide translocase（ANT）is a transport protein responsible for the conduction of energy molecules in the inner membrane of mitochondria，playing a vital role in the energy metabolism. In order to study the role of ANT gene in the molting of crustacean，a full-length cDNA of ANT gene（GenBank access number：KM921660）was cloned from Portunus trituberculatus using RT-PCR and RACE. Sequence analysis showed that it was 1 414 bp long，including a 132 bp 5' non-coding region，a 352 bp 3' non-coding region，and a 930 bp coding region，and encoded 309 amino acids. The phylogenetic comparison of ANT gene sequence between P. trituberculatus and other species revealed that ANT gene from P. trituberculatus and other species clustered as one same branch，and the similarity with Scylla paramamosain was up to 96%. Amino acid alignment proved that it had 3 conserved mitochondrial transmembrane domains，forming a channel for the conduction of energy molecules，and catalyzing transmembrane exchange between ATP in mitochondria and ADP in cytoplasm. Real-time PCR results indicated that ANT gene expressed in all 10 different tissues with the highest expression in muscle，while quite low in all other tissues，and there were significant differences among the expressions of the tissues（P<0.05）. During the whole molting process，the level of ANT in muscle reached the maximum at postmolt（stage A），then began to decline until the least during intermolt（stage C），and then gradually rose until the second peak at stage D1，then declined again. The combined result indicated that ANT gene was closely correlated with the activity of muscle of P. trituberculatus，and might play an essential role in the molting.