| Inhibitor of apoptosis proteins (IAPs) constitute a family of proteins that contain one to three baculovirus IAP repeats (BIR). This IAP protein family ensure cell viability directly binding to caspases through the BIR domain and regulating their activities in an ubiquitin-dependent manner. However, they are also regulated by IAP antagonists. Two iap gene called Tiap1 and Tiap2 were cloned from Tribolium castaneum by RT-PCR and sequenced, to investigate the IAP regulation pathway in coleoptera. They are 1017bp and 1485bp in length, respectively. The putative protein TIAP1 contains two BIR domains and one RING finger domain, while the other putative TIAP2 has three BIR domains and one RING finger domain. By comparison with the known proteins in the NCBI, TIAP1 shared moderate identity with Bombyx mori IAP (GENE ID:692576, 55.95%) and TIAP2 shared moderate identity with Drosophila IAP (GENE ID:36748, 53.37%). Multiple sequence alignment was set up with homologs from other species in NCBI. Pphylogenetic tree analysis showed that Tribolium castaneum TIAP1 and TIAP2 are grouped into two clades because of the different amount of the BIR domain,,and the BIR2 domain of TIAP1 was similar with the BIR2 domain of TIAP2 rather than the BIR2 domain of the TIAP2, suggesting that a unique loss event for BIR sequence of one iap copy happened before insect speciation.In order to study more about the regular pattern of iap gene in Tribolium castaneum, expression patterns of two iap genes in seven larval stages of Tribolium castaneum were analyzed by semi-quantitative RT-PCR. The result showed that these genes were expressed in all tested larval stages of Tribolium castaneum. In order to study the ruction of these two genes, the Bac to Bac system was used to make the combation of Recombinant Bacmid. Now three Recombinant Bacmid Bacmid-Tiap1, Bacmid-Tiap2, Bacmid-Mx were set up. All these works are benefit for the study of the IAP pathway in coleoptera insects.
|
PDF Full Text Request