Wang Qianqian, Zhao Di, Wang Ling, Sang Yuxuan, Meng Hailan, Wang Qi, Shan Hu, Liu Fuxiao, Geri Letu
College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010011, China.
College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China.
Virology. 2023 Feb;579:67-74. doi: 10.1016/j.virol.2022.12.009. Epub 2022 Dec 30.
To clarify whether Senecavirus A (SVA) has the potential of alternative translation, an extra G residue was inserted into an SVA cDNA clone, resultantly generating an "AUGAUG" motif. The second AUG is the authentic SVA initiation codon, whereas the first AUG is a putative one. Subsequently, eighteen nucleotides were inserted one by one between AUG and AUG for reconstructing cDNA clones. The test of virus recovery showed that three replication-competent SVAs, whose AUG/AUG-flanked sequences were not multiples of three nucleotides, were successfully rescued from their individual cDNA clones. The wild-type SVA possesses a UUUUU motif within the polyprotein-encoding region. Sanger sequencing showed that these three replication-competent SVAs harbored one or two extra U residues in the UUUUU motif, implying that polyprotein translation was initiated from the putative AUG, and the authentic AUG would be inactivated. This is probably attributed to the lack of ribosome scanning along an SVA genome.
为了阐明A组赛尼卡病毒（SVA）是否具有可变翻译的潜力，在一个SVA cDNA克隆中插入了一个额外的G残基，从而产生了一个“AUGAUG”基序。第二个AUG是SVA真正的起始密码子，而第一个AUG是一个推定的起始密码子。随后，在AUG和AUG之间逐个插入18个核苷酸以重建cDNA克隆。病毒拯救试验表明，从其各自的cDNA克隆中成功拯救出了三种具有复制能力的SVA，其AUG/AUG侧翼序列不是三个核苷酸的倍数。野生型SVA在多聚蛋白编码区内具有一个UUUUU基序。桑格测序表明，这三种具有复制能力的SVA在UUUUU基序中含有一个或两个额外的U残基，这意味着多聚蛋白翻译是从推定的AUG起始的，而真正的AUG将失活。这可能归因于缺乏沿SVA基因组的核糖体扫描。
