Cleavage of Akabane virus S RNA in the brain of infected ruminants.
Since 2002 there has been a rise in arthrogryposis/hydranencephaly incidence in Israel, caused by Akabane viruses (AKAV) and possibly by Aino viruses. In response to the outbreak, serological, molecular-diagnostic and research tools were developed. AKAV sequences were detected by real-time RT-PCR in the brain tissue of 2 out of 20 tested calves and lambs that suffered from hydranencephaly. When the S segments from the two infected calves were characterized, it was concluded that the S genome were cleaved. In order to localize the cleavage site, the 3' segment of the S genome was cloned, sequenced, and found to be 430 bases long, which indicates a cleavage site between nucleotides 430 and 431 of the S segment in the antigenome. This cleavage site was found to be specific and not a result of degradation processes. Analysis of the S segment RNA secondary structure revealed that the cleavage site was located on a loop structure. Furthermore, flunking the cleavage site there are stretches of 7 or 8 bases long that were part of a stem with low free energy, which could stabilize the loop, making it accessible to an, as yet, uncharacterized cleavage mechanism.
Levin
Aviad
A
Molecular Virology Department, Faculty of Medicine, Hebrew University of Jerusalem, 12272, Jerusalem 91120, Israel.
Rubinstein-Guini
Marisol
M
Kuznetzova
Larisa
L
Stram
Yehuda
Y
D000818:Animals; D001921:Brain / Q000821:virology*; D002043:Bunyaviridae / Q000235:genetics* / Q000302:isolation & purification; D002044:Bunyaviridae Infections / Q000662:veterinary* / Q000821:virology; D002417:Cattle; D002418:Cattle Diseases / Q000821:virology*; D016679:Genome, Viral; D007557:Israel; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017423:Sequence Analysis, RNA; D012756:Sheep; D012757:Sheep Diseases / Q000821:virology*
D012367:RNA, Viral