Characterization of Nuclear Protein SP110b

• Main Authors: Jia-Shiun Leu, 呂嘉勳
• Other Authors: Bo-Shiun Yan
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/07143051037059876469

碩士 === 國立陽明大學 === 微生物及免疫學研究所 === 97 === It is estimated that one-third of people infected with pathogen Mycobacterium tuberculosis (Mtb) and fewer than 10% of them progress to tuberculosis in their lifetime. In a mouse model, intracellular pathogen resistance 1 (Ipr1) gene, which mediates host innate immunity to Mtb infection, has been identified within sst1 (susceptibility to tuberculosis 1) locus. In human, SP110b is the closest homology protein of IPR1 (41% identity), and its gene localizes in region of human chromosome 2. IPR1 and SP110b are both interferon inducible proteins, and they may have the same function involved in immunity in mice and human. In this study, we used dual-promoter lentiviral system to establish the stable cell clones, in which the expression of eGFP-SP110b protein can be induced in presence of doxycycline. The stability of eGFP-SP110b protein is increased after IFN�� treatment. The proteins interacting with SP110b were further characterized by co-immunoprecipating the protein complex interacting with eGFP-SP110b. The data reveal that SP110b protein complex may be more stable in pro-inflammation environment. We will identify the proteins interacting with SP110b by MS/MS analysis. Using the lentiviral expression system, we also demonstrated the OAS1 (2,5- oligoadenylate synthetase 1), which is involved in an RNase L-mediated apoptotic pathway, interacted with SP110b protein in 293T and THP1 cells. However, the role of SP110b in the OAS1/RNase L pathway is still unclear. We hypothesize that SP110b regulates apoptosis through the OAS1/RNase L pathway after IFN treatment.