Evaluating the role of CRM1-mediated export for adenovirus gene expression.
A complex of the Adenovirus (Ad) early region 1b 55-kDa (E1b-55kDa) and early region 4 ORF6 34-kDa (E4-34kDa) proteins promotes viral late gene expression. E1b-55kDa and E4-34kDa have leucine-rich nuclear export signals (NESs) similar to that of HIV Rev. It was proposed that E1b-55kDa and/or E4-34kDa might promote the export of Ad late mRNA via their Rev-like NESs, and the transport receptor CRM1. We treated infected cells with the cytotoxin leptomycin B to inhibit CRM1-mediated export; treatment initially delays the onset of late gene expression, but this activity completely recovers as the late phase progresses. We find that the E1b-55kDa NES is not required to promote late gene expression. Previous results showed that E4-34kDa-mediated late gene expression does not require an intact NES (J. Virol. 74 (2000), 6684-6688). Our results indicate that these Ad regulatory proteins promote late gene expression without intact NESs or active CRM1.
Carter
Christoph C
CC
Department of Microbiology, 32 Pearson Hall, Miami University, Oxford, OH 45056, USA.
Izadpanah
Reza
R
Bridge
Eileen
E
D021581:Active Transport, Cell Nucleus; D017501:Adenovirus E1B Proteins / Q000235:genetics / Q000378:metabolism*; D017504:Adenovirus E4 Proteins / Q000235:genetics / Q000378:metabolism*; D000260:Adenoviruses, Human / Q000472:pathogenicity*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D015967:Gene Expression Regulation, Viral; D006367:HeLa Cells; D006801:Humans; D028884:Karyopherins / Q000378:metabolism*; D012367:RNA, Viral / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear; D000097606:Exportin 1 Protein
D017501:Adenovirus E1B Proteins; D017504:Adenovirus E4 Proteins; D005231:Fatty Acids, Unsaturated; D028884:Karyopherins; D012367:RNA, Viral; D018160:Receptors, Cytoplasmic and Nuclear; D000097606:Exportin 1 Protein; C038753:leptomycin B