RESUMEN
Objective@#To study the intracellular location and characteristic of SFTSV NP protein in different phases using mini singlet oxygen generator (miniSOG) labeling technique.@*Methods@#MiniSOG is a recently-invented genetically-encoded tag for EM. MiniSOG-fused SFTSV NP (NPSOG) gene was cloned by PCR, and inserted into pcDNA3.0 plasmid to form pTPL-NPSOG, which was used to transfect 293 cells. The transfected cells of different phases were fixed in 2.5% glutaraldehyde in situ, stained with DAB through the photooxidation activity of miniSOG, and used to prepare ultrathin sections. Intracellular location and characteristic of SFTSV NP protein in different phases were studied by observing the sections under transmission electron microscope.@*Results@#After transfecting the plasmid with NPSOG to 293 cells, NP protein was expressed in cytoplasm and peri nucleus, and gradually aggregated, which connected with endoplasmic reticulum and Golgi apparatus to form larger volume and irregular inclusion bodies in cytoplasm. No obvious subcellular structure changes were found.@*Conclusions@#The SFTSV nucleoprotein can be expressed separately to form inclusion bodies without the assistance of other viral proteins. The formation of inclusion bodies requires the directional movement and aggregation of a certain number of NP proteins, which may involve the interaction of NP protein and host organelles during this period.
RESUMEN
Objective@#To establish a method of correlative light and electron microscopy (CLEM) to study the intracellular location of adenovirus protein IX.@*Methods@#MiniSOG (mini singlet oxygen generator) is a recently-invented genetically-encoded tag for CLEM. MiniSOG-fused adenovirus IX gene (IXSOG) was cloned by PCR, and inserted into pcDNA3 plasmid to form pTPL-IXSOG, which was used to transfect 293 cells. IXSOG expressing cells could be distinguished under fluorescence microscope due to the emission of green fluorescence of miniSOG. The transfected cells were fixed in 2.5% glutaraldehyde in situ, stained with diaminobenzidine(DAB) through the photooxidation activity of miniSOG, and used to prepare ultrathin sections. Intracellular location of IXSOG was studied by observing the sections under transmission electron microscope.@*Results@#Eukaryotic expression plasmid carrying IXSOG fusion gene was constructed. IXSOG expressing cells were selected for DAB photooxidation and preparation of ultrathin sections. IXSOG fusion mainly formed punctate aggregations or inclusions in the nucleus.@*Conclusions@#The correlative light and electron microscopy method based on miniSOG was successfully established, and it could be used to study the intracellular localization of viral proteins.