Chicken RNA-binding protein T-cell internal antigen-1 contributes to stress granule formation in chicken cells and tissues

T-cell internal antigen-1 (TIA-1) has roles in regulating alternative pre-mRNA splicing, mRNA translation, and stress granule (SG) formation in human cells. As an evolutionarily conserved response to environmental stress, SGs have been reported in various species. However, SG formation in chicken cells and the role of chicken TIA-1 (cTIA-1) in SG assembly has not been elucidated. In the present study, we cloned cTIA-1 and showed that it facilitates the assembly of canonical SGs in both human and chicken cells. Overexpression of the chicken prion-related domain (cPRD) of cTIA-1 that bore an N-terminal green fluorescent protein (GFP) tag (pntGFP-cPRD) or Flag tag (pFlag-cPRD) induced the production of typical SGs. However, C-terminal GFP-tagged cPRD induced notably large cytoplasmic granules that were devoid of endogenous G3BP1 and remained stable when exposed to cycloheximide, indicating that these were not typical SGs, and that the pntGFP tag influences cPRD localization. Finally, endogenous cTIA-1 was recruited to SGs in chicken cells and tissues under environmental stress. Taken together, our study provide evidence that cTIA-1 has a role in canonical SG formation in chicken cells and tissues. Our results also indicate that cPRD is necessary for SG aggregation.

Proteomic analysis of chicken peripheral blood mononuclear cells after infection by Newcastle disease virus

Characteristic clinical manifestations of Newcastle disease include leukopenia and immunosuppression. Peripheral blood mononuclear cells (PBMCs) are the main targets of Newcastle disease virus (NDV) infection. To survey changes in proteomic expression in chicken PBMCs following NDV infection, PBMC proteins from 30 chickens were separated using two-dimensional electrophoresis (2-DE) and subjected to mass spectrometry analysis. Quantitative intensity analysis showed that the expression of 78 proteins increased more than two-fold. Thirty-five proteins exhibited consistent changes in expression and 13 were identified as unique proteins by matrix assisted laser desorption ionization-time of flight mass spectrometer/mass spectrometer including three that were down-regulated and 10 that were up-regulated. These proteins were sorted into five groups based on function: macromolecular biosynthesis, cytoskeleton organization, metabolism, stress responses, and signal transduction. Furthermore, Western blot analysis confirmed the down-regulation of integrin-linked kinase expression and up-regulation of lamin A production. These data provide insight into the in vivo response of target cells to NDV infection at the molecular level. Additionally, results from this study have helped elucidate the molecular pathogenesis of NDV and may facilitate the development of new antiviral therapies as well as innovative diagnostic methods.

Mutation of lambdapL/pR-cI857 system for production of bacterial ghost in Escherichia coli / 生物工程学报

Bacterial ghost is intact envelope of Gram-negative bacteria, which is produced by the function of the lysis gene E from bacteriophage PhiX174. The expression of the lysis gene E is usually controlled by the thermosensitive lambdapL/pR-cI857 promoter. In this study, we described a mutation (T --> C) at the ninth nucleotide of the OR2 in the lambdapR promoter of the lambdapL/pR-cI857 system by overlap PCR. The bacteriolytic assay showed that the mutation in the lambdapL/pR-cI857 system enhanced the temperature of repressing the expression of gene E up to 37 degrees C. The lysis efficiency of altered lambdapR promoter in Escherichia coli DH5a and avian pathogenic E. coli DE17 was up to 99.9%. The expanded range of temperature will benefit for the production of bacterial ghost.