CHARACTERIZATION OF THE SPODOPTERA-FRUGIPERDA TATA-BINDING PROTEIN - NUCLEOTIDE-SEQUENCE AND RESPONSE TO BACULOVIRUS INFECTION

A cDNA clone containing a 921 bp open-reading frame (307 amino acids; 34 kDa) homologous to the TATA-binding protein (TBP) was isolated and sequenced from a Spodoptera frugiperda cell line that is commonly used in the baculovirus expression system. Analysis of the S. frugiperda T BP (SfTBP) sequence showed that the amino-terminal portion of SfTBP di verged significantly from that of other TBP sequences including Drosop hila melanogaster whereas the carboxy-terminal sequence was highly con served. Southern blot analysis indicated that SfTBP was encoded by a s ingle gene in the S. frugiperda genome. Northern blot analysis indicat ed that steady-state levels of the 1.3 kb SfTBP transcript declined by 24 h post-infection corresponding to the time of virus-induced inhibi tion of host-cell transcription. Corresponding western blot analysis s howed that TBP protein levels remain constant up to 72 h post-infectio n.