title: Molecular cloning and characterization of Hearm caspase-1 from Helicoverpa armigera.
abstract: Members of the caspase family play a central and evolutionary role in programmed cell death (PCD), which removes unwanted, damaged and dangerous cells during development to maintain homeostasis. In this paper, we describe the cloning and characterization of a caspase from the cotton bollworm, Helicoverpa armigera, named Hearm caspase-1. The 1,350 bp full-length cDNA contains an 885 bp open reading frame (ORF) that encodes a Hearm caspase-1 proenzyme of 294 amino acids. The deduced protein is highly homologous to Spodoptera frugiperda Sf caspase-1 and Drosophila melanogaster ICE and has the highly conserved pentapeptide QACQG, the recognized catalytic site of caspases, suggesting that it is an effector caspase of the cotton bollworm. Northern blot and RT-PCR analyses demonstrate that Hearm caspase-1 is expressed in embryos and the fat body, midgut and haemocytes of feeding and wandering larvae. Expression of Hearm caspase-1 in the haemocytes appears to be correlated with the pulse of ecdysone, and it is up-regulated by ecdysone agonist RH-2485, implying that Hearm caspase-1 activation is regulated by ecdysone.
authors.affiliation: School of Life Sciences, Shandong University, Jinan, China.
authors.forename: Dantong
authors.initials: D
authors.lastname: Yang
authors.forename: Lianqin
authors.initials: L
authors.lastname: Chai
authors.forename: Jinxing
authors.initials: J
authors.lastname: Wang
authors.forename: Xiaofan
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D020170:Caspase 1 / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D006434:Hemocytes / Q000201:enzymology; D006801:Humans; D007814:Larva / Q000201:enzymology / Q000235:genetics; D007915:Lepidoptera / Q000196:embryology / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D008969:Molecular Sequence Data; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D018076:DNA, Complementary; D020170:Caspase 1