MOLECULAR CLONING OF LVANT2 GENE AND ITS EXPRESSION PATTERN BY COLD INDUCTION

To study the molecular mechanism of cold tolerance of Litopenaeus`vannamei, a 360 bp EST was isolated from suppression subtractive hybridization library of hepatopancreas which treated by low temperature. The 360 bp EST shared highly homology with ANT2 gene of other species, so we named it Litopenaeus vannamei ANT2 gene (LVANT2). Then we cloned whole cDNA sequence of PVANT2 from a hepatopancreas cDNA library. The LVANT2 gene was 1540 bp with a 1011 bp open reading frame encoding a peptide of 309aa. Tissue expression pattern by real-time PCR revealed that LVANT2 mRNA existed in heart, hepatopancreas, muscle, stomach, intestinal and eyestalk but mainly existed in muscle tissue. Cold induction by different temperatures revealed that LVANT2 mRNA expression started to increase after 15℃ treatment for 36 hours, and then decreased after 13℃ treatment for 36 hours, but increased again after 11℃ treatment. As for 13℃ treatment for different times, the expression pattern changed during the first 12 hours, but the expression with low temperature treatment for 24 hours and 36 hours was almost the same with the room temperature. The low temperature induction expression pattern demonstrated that LVANT2 may function in cold tolerance of Litopenaeus vannamei.