The Strica Homolog AaCASPS16 Is Involved in Apoptosis in the Yellow Fever Vector, Aedes albopictus

Caspases are a family of cysteine proteases playing essential roles during apoptosis. Seven caspases identified in Drosophila were Dronc, Dredd, Strica, Dcp-1, Decay, Drice and Damm. Among them, Strica is an insect-specific caspase containing a long serine- and threonine- rich prodomain, of which function is not yet well studied. Here we identified a homolog of strica from Aedes albopictus, named as Aacasps16. Aacasps16 encoded a protein containing a putative serine- and threonine-rich prodomain and a well conserved caspase catalytic domain. AaCASPS16 shared high identity with dipteran insects Strica homologs. Alignment showed that the closest relative of AaCASPS16 was Aedes aegypti AeCASPS16. The expression profiles of Aacasps16 during developmental and adult stages were analyzed. Purified recombinant AaCASPS16 exhibited the highest caspase activity to WEHD, which is the substrate preferred by human caspase-9. AaCASPS16 induced apoptosis when over-expressed in C6/36 cells. AaCASPS16 was processed during apoptosis induced by actinomycin D and ultraviolet irradiation treatment, whereas partial silencing of Aacasps16 reduced actinomycin D- and ultraviolet irradiation-triggered apoptosis in C6/36 cells. Taken together, our study identified AaCASPS16 as a novel apoptotic caspase in Aedes albopictus.

[1]  B. J. Olson,et al.  Rapid selection against arbovirus-induced apoptosis during infection of a mosquito vector , 2015, Proceedings of the National Academy of Sciences.

[2]  A. Kale,et al.  Apoptotic mechanisms during competition of ribosomal protein mutant cells: roles of the initiator caspases Dronc and Dream/Strica , 2015, Cell Death and Differentiation.

[3]  S. Nair,et al.  Mechanisms of Postecdysis‐Associated Programmed Cell Death of Peptidergic Neurons in Drosophila melanogaster , 2013, The Journal of comparative neurology.

[4]  Sharad Kumar,et al.  Developmentally programmed cell death in Drosophila. , 2013, Biochimica et biophysica acta.

[5]  C. Lowenberger,et al.  Differential Expression of Apoptosis Related Genes in Selected Strains of Aedes aegypti with Different Susceptibilities to Dengue Virus , 2013, PloS one.

[6]  N. Kyprianou,et al.  Proteasomal regulation of caspase-8 in cancer cell apoptosis , 2013, Apoptosis.

[7]  Benjamin F. Cravatt,et al.  Functional Interplay between Caspase Cleavage and Phosphorylation Sculpts the Apoptotic Proteome , 2012, Cell.

[8]  M. Zvelebil,et al.  Ubiquitylation of the initiator caspase DREDD is required for innate immune signalling , 2012, The EMBO journal.

[9]  L. Tian,et al.  20-hydroxyecdysone upregulates apoptotic genes and induces apoptosis in the Bombyx fat body. , 2012, Archives of Insect Biochemistry and Physiology.

[10]  W. Zong,et al.  Inhibition of Protein Degradation Induces Apoptosis through a Microtubule-Associated Protein 1 Light Chain 3-Mediated Activation of Caspase-8 at Intracellular Membranes , 2011, Molecular and Cellular Biology.

[11]  C. Paupy,et al.  Aedes albopictus, an arbovirus vector: from the darkness to the light. , 2009, Microbes and infection.

[12]  G. H. Coombs,et al.  Characterization of unusual families of ATG8-like proteins and ATG12 in the protozoan parasite Leishmania major , 2009, Autophagy.

[13]  C. Blair,et al.  Annotation and expression profiling of apoptosis-related genes in the yellow fever mosquito, Aedes aegypti. , 2007, Insect biochemistry and molecular biology.

[14]  H. Steller,et al.  The Drosophila caspases Strica and Dronc function redundantly in programmed cell death during oogenesis , 2007, Cell Death and Differentiation.

[15]  R. Ueda,et al.  Systematic in vivo RNAi analysis of putative components of the Drosophila cell death machinery , 2006, Cell Death and Differentiation.

[16]  T. Scott,et al.  Apoptosis in mosquito midgut epithelia associated with West Nile virus infection , 2006, Apoptosis.

[17]  Yu Xue,et al.  GPS: a comprehensive www server for phosphorylation sites prediction , 2005, Nucleic Acids Res..

[18]  F. Kafatos,et al.  Arthropod-borne diseases: vector control in the genomics era , 2005, Nature Reviews Microbiology.

[19]  G. Salvesen,et al.  The protein structures that shape caspase activity, specificity, activation and inhibition. , 2004, The Biochemical journal.

[20]  F. Baneyx,et al.  Recombinant protein folding and misfolding in Escherichia coli , 2004, Nature Biotechnology.

[21]  N. Gratz,et al.  Critical review of the vector status of Aedes albopictus , 2004, Medical and veterinary entomology.

[22]  Yigong Shi Caspase Activation Revisiting the Induced Proximity Model , 2004, Cell.

[23]  J. Denault,et al.  Apoptosis in Biochemistry and Structural Biology. 3-8 February 2004, Keystone, CO, USA. , 2004, IDrugs : the investigational drugs journal.

[24]  G. Salvesen,et al.  Mechanisms of caspase activation. , 2003, Current opinion in cell biology.

[25]  D. Green,et al.  A unified model for apical caspase activation. , 2003, Molecular cell.

[26]  Thomas D. Schmittgen,et al.  Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method. , 2001, Methods.

[27]  H. Richardson,et al.  STRICA, a novel Drosophila melanogaster caspase with an unusual serine/threonine-rich prodomain, interacts with DIAP1 and DIAP2 , 2001, Cell Death and Differentiation.

[28]  J. Doumanis,et al.  The fly caspases , 2000, Cell Death and Differentiation.

[29]  Sharad Kumar,et al.  DRONC, an ecdysone-inducible Drosophila caspase. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[30]  G. Salvesen,et al.  Caspase assays: identifying caspase activity and substrates in vitro and in vivo. , 2008, Methods in enzymology.

[31]  S. Higgs,et al.  Salivary gland morphology and virus transmission during long-term cytopathologic West Nile virus infection in Culex mosquitoes. , 2007, The American journal of tropical medicine and hygiene.