(I)nteraction of influenza virus NS1 protein and the human homologue of Staufen in vivo and in vitro

Citation
Am. Falcon et al., (I)nteraction of influenza virus NS1 protein and the human homologue of Staufen in vivo and in vitro, NUCL ACID R, 27(11), 1999, pp. 2241-2247
Citations number
48
Categorie Soggetti
Biochemistry & Biophysics
Journal title
NUCLEIC ACIDS RESEARCH
ISSN journal
03051048 → ACNP
Volume
27
Issue
11
Year of publication
1999
Pages
2241 - 2247
Database
ISI
SICI code
0305-1048(19990601)27:11<2241:(OIVNP>2.0.ZU;2-K
Abstract
A screening for human proteins capable of interacting with influenza virus NS1 has been carried out using the two-hybrid genetic trap in yeast. A cDNA corresponding to the human homologue of Drosophila melanogaster Staufen pr otein (hStaufen) was isolated that fulfilled all genetic controls of the tw o-hybrid protocol. Using a hStaufen cDNA isolated from a lambda human libra ry, the interaction of hStaufen and NS1 proteins was characterised in vivo and in vitro. Co-transfection of NS1 cDNA and a partial cDNA of hStaufen le d to the relocalisation of recombinant hStaufen protein from its normal acc umulation site in the cytoplasm to the nuclear location of NS1 protein. NS1 and hStaufen proteins could be co-immunoprecipitated from extracts of co-t ransfected cells and from mixtures of extracts containing either protein, a s well as from extracts of influenza virus-infected cells, Furthermore, bot h proteins co-localised in the ribosomal and polysomal fractions of influen za virus-infected cells. The interaction was also detected in pull-down exp eriments using a resin containing purified hStaufen and NS1 protein transla ted in vitro, Deletion mapping of the NS1 gene indicated that a mutant prot ein containing the N-terminal 81 amino acids is unable to interact with hSt aufen, in spite of retaining full RNA-binding capacity. These results are d iscussed in relation to the possible mechanisms of action of hStaufen and i ts relevance for influenza virus infection.