The mouse interferon-inducible gene Ifi204 product interacts with the Tpr protein, a component of the nuclear pore complex.
We have used yeast two-hybrid screening to isolate cDNA-encoding proteins interacting with the protein encoded by the interferon (IFN)-inducible gene Ifi204. Four independent overlapping clones were isolated from an NIH3T3 cDNA library. The largest clone encoded a protein (1203 amino acids in length) sharing 94% identity with the C-terminal portion of the human translocated promoter region (Tpr) protein. Northern blot analysis revealed a 7.5-kilobase mRNA present in both mouse and human cell lines. In addition, in vivo interaction was demonstrated by coimmunoprecipitation experiments. Anti-Tpr polyclonal monospecific antibodies (Ab) used for immunofluorescence staining labeled the nuclear envelope (NE) in a punctate pattern characteristic of nucleoporins and also yielded staining throughout the nuclear interior. The intranuclear Tpr occurred in apparently discrete foci. When superimposed on optical sections obtained with anti-p204 Abs, these colocalized, with the sole exception of the nucleolar compartment stained by the anti-p204 Abs only. Although the specific function of Tpr is not defined, it appears to mediate p204 translocation from the cytoplasmic to the nuclear compartment following IFN treatment.
De Andrea
Marco
M
Department of Medical Sciences, Medical School, 28100-Novara, Italy.
Zannetti
Claudia
C
Noris
Emanuela
E
Gariglio
Marisa
M
Azzimonti
Barbara
B
Landolfo
Santo
S
D016475:3T3 Cells; D000818:Animals; D001665:Binding Sites; D015152:Blotting, Northern; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D022022:Nuclear Pore / Q000502:physiology*; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics* / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D014162:Transfection
D018076:DNA, Complementary; C489664:Ifi16 protein, mouse; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D011994:Recombinant Proteins; C073597:TPR protein, human; C076700:IFI16 protein, human