Effects of 1,8-diaminooctane on the FIV Rev regulatory system.
Proper function of the Rev regulatory system is essential for the replication of lentiviruses, including feline immunodeficiency virus (FIV) and human immunodeficiency virus type 1 (HIV-1). Specifically, Rev affects the overall stability of viral mRNAs that encode necessary structural and enzymatic proteins. In turn, the eukaryotic initiation factor (eIF-5A) is indispensable for Rev function and is the only known protein whose biologically active form requires the unique amino acid, hypusine. Because 1,8-diaminooctane blocks the formation of hypusine by disrupting the cellular enzyme, deoxyhypusine synthase, thereby preventing activation of eIF-5A, we investigated the effects of 1,8-diaminooctane on posttranscriptional regulation. These are the first results to demonstrate that diaminooctane significantly reduced viral replication in a dose-dependent manner, even under conditions of contact inhibition, diminishing the compound's effect on cell proliferation. Similarly, the addition of increased concentrations of diaminooctane caused a reduction in the expression of a Rev-dependent CAT system without affecting a Rev-independent CAT system. At the RNA level, exposure of chronically infected CrFK cells to increasing concentrations of diaminooctane substantially decreased the levels of unspliced and singly spliced viral mRNAs and increased the relative amounts of multiply spliced transcripts in the cytoplasm. The findings of this study are the first demonstration that FIV, similar to HIV-1, requires eIF-5A for efficient Rev function and that small molecule intervention can indirectly target this lentivirus regulatory system.
Hart
Richard A
RA
Vaccine Research Institute of San Diego, San Diego California 92177, USA.
Billaud
Jean-Noël
JN
Choi
Sam J
SJ
Phillips
Tom R
TR
D000818:Animals; D002415:Cats; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003959:Diamines / Q000494:pharmacology*; D015694:Gene Products, rev / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D016089:Immunodeficiency Virus, Feline / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D014779:Virus Replication / Q000187:drug effects
D003959:Diamines; D015694:Gene Products, rev; D012333:RNA, Messenger; C008697:octamethylenediamine