Cloning And Analysis Of Slpi Caspase-1

Apoptosis is the current hot areas of life science research.The mechanism of apoptosis in mammals and C.elegans has made great progress.,but for the insect cell apoptosis signaling pathways are still many issues to be exploring.The molecular mechanism of apoptosis in the process of biological evolution is highly conserved.There are many similarities between insect cells apoptosis pathway and that of mammalian. The differences in the apoptosis pathway between Drosophila melanogaster and mammals are found, which presenting a new perspective on the development of apoptosis. In this study, we cloned Spodoptera litura Caspase gene full-length cDNA for exploring the role of gene in apoptosis.In this study, according to the highly conserved genomic sequence of Spodoptera littoralis and Spodoptera frugiperda, We designed and synthesized a pair of primers. The cDNA encoding caspase of Spodoptera litura was amplified from the total RNA extracted from SL-1 cells by RT-PCR technique. Firstly, We obtained a 419bp fragment. Based on this fragment pairs of 3'- and 5'-RACE specific primers were designed. The full-length cDNA sequence of caspase gene was obtained by 3'-RACE and 5'-RACE from Spodoptera litura. The acquired gene was 1241bp in full length, including 5'untranslated region of 154bp, 3' untranslated region of 174bp (excluding poly(A)).The sequence contains an ORF (open reading frame) consisted of 891bp and encoded 296 amino acids. Corresponding sequence comparisons of Spodoptera litura with Spodoptera frugiperda and Spodoptera littoralis were 92% and 99%,The phylogenteic trees constructed on the basis of caspase using DNAstar software suggests that the relationship of caspase between Spodoptera litura and Spodoptera littoralis is the same,and has the lowest homology with Bombyx mori ICE-5.As is true of many proteases, caspases are present in cells as inactive zymogens and consisit of QACXG(X is R,Q,or G) pentapeptide sequecce. According to this study, the sequence of caspase contains QACQG.. The cDNA of caspase gene was cloned successfully from Spodoptera litura has an important role on further study of the whole structure of Spodoptera litura caspase genes, gene expression and regulation.