Recombinant expression plasmid of pET-28a (+)-goIL-2 was constructed by inserting the goose IL-2 gene without the signal peptide sequence into the prokaryotic expression vector pET-28a (+), and transformed into the bacterial competent E. coli BL21 (DE3) cells for expression. After IPTG induction, an expected protein band with molecular weight of 15.0 kD was observed on SDS-PAGE gel, recognized by monoclonal antibody against goose IL-2 in western-blotting assay. In the pET-28a (+) expression system, much of the recombinant goose IL-2 (rgoIL-2) was found in inclusion bodies with a portion of soluble protein. The monomer and multimers of soluble goose interleukin 2 proteins were observed in native electrophoresis. The rgoIL-2 proteins were purified by Ni-NTA column under a native condition. The rgoIL-2 soluble protein monomer was isolated by a quick protein isolation and purification system of AKTA FPLC and identified by native PAGE. Bioactivity analysis showed that the rgoIL-2 monomer stimulated the proliferation of goose lymphocytes in vitro. This will establish a basis for further study about the biological function and clinical application of goose IL-2.
Animals ; Escherichia coli ; genetics ; metabolism ; Geese ; genetics ; Inclusion Bodies ; metabolism ; Interleukin-2 ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; Solubility

Objective To investigate the rescue effect of Drp1 gene over-expression on drosophila models of Parkinson's disease (PD) and their specific mechanism using iTRAQ-based proteomic technology. Methods The drosophilae from 3 groups, control group, PD group (PINK1 mutant), and rescue group (PINK1 mutant+Drp1 over-expression) were cultured at routine ways. The wing shape and movement ability of drosophilae were observed, and the percentages of drosophilae having abnormal wings and normal flight were calculated. The proteomic changes were determined by iTRAQ technology; the functions and signaling pathways of the differential expressed proteins were analyzed by GO and KEGG pathway enrichment analyses. Results Percentage of drosophilae having abnormal wings in the rescue group (2.60％±0.47％) was significantly decreased as compared with that in the PD group (82.40％±12.47％, P<0.05), and the percentage of drosophilae having normal flight in the rescue group (89.70％±7.76％) was significantly increased as compared with that in the PD group (3.30％±1.69％, P<0.05). A total of 3630 proteins were identified using iTRAQ; 282 differential expressed proteins between the PD group and control group were detected, which mainly were iron ion related proteins; 170 differential expressed proteins between the PD group and rescue group were detected, which mainly were zinc ion related proteins. GO and KEGG pathway enrichment analyses on these co-differential expressed proteins revealed that 21％ proteins had metal ion binding activity, especially zinc ion. Conclusion Abnormal iron homeostasis, especially zinc homeostasis, participates in PD pathophysiological processes and over-expressing Drp1 rescued PD processes.

We studied the effect of celastrol on the proliferation and apoptosis of adult T-cell leukemia (ATL) cells. After treating adult T-cell leukemia cell lines with different concentrations of celastrol, we analyzed the cell proliferation by MTT and colony formation assays. Flow cytometry was conducted to detect cell apoptosis by Annexin V-FITC/PI staining. Western blotting and dual-luciferase reporter assay were done to study the mechanism how celastrol suppressed the growth of adult T-cell leukemia cells. Celastrol could significantly inhibit the proliferation of adult T-cell leukemia cells, and induce apoptosis of ATL cells. With the increase of the concentration of celastrol, the ratio of Bax/Bcl-2 protein was up-regulated. The Caspase-3/7 protein was cleaved and activated after treatment with celastrol. Moreover, the expression of HTLV-1-encoded viral protein Tax was significantly inhibited in the celastrol treated cells. Taken together, these results indicated that celastrol effectively inhibited the proliferation of adult T-cell leukemia cells by regulating the expression of Bcl-2 family protein, and induced cell apoptosis by activating Caspase dependent pathway. In addition, celastrol could inhibit the expression of viral protein Tax. This study will provide an experimental basis for the clinical application of celastrol in the treatment of adult T-cell leukemia.