Department of Microbiology, Clayton Campus, Monash University, Clayton 3800, Australia.
Computational Biology Group, Max-Planck-Institute of Biochemistry, 82152 Martinsried, Germany.
Viruses. 2021 Nov 29;13(12):2388. doi: 10.3390/v13122388.
Halovirus HF2 was the first member of the genus to have its genome fully sequenced, which revealed two classes of intergenic repeat (IR) sequences: class I repeats of 58 bp in length, and class II repeats of 29 bp in length. Both classes of repeat contain AT-rich motifs that were conjectured to represent promoters. In the present study, nine IRs were cloned upstream of the reporter gene, and all displayed promoter activity, providing experimental evidence for the previous conjecture. Comparative genomics showed that IR sequences and their relative genomic positions were strongly conserved among other members of the same virus genus. The transcription of HF2 was also examined by the reverse-transcriptase-PCR (RT-PCR) method, which demonstrated very long transcripts were produced that together covered most of the genome, and from both strands. The presence of long counter transcripts suggests a regulatory role or possibly unrecognized coding potential.
噬纤维菌 HF2 是首个全基因组测序的属成员，其基因组中包含两类基因间重复（IR）序列：长度为 58 个碱基的 I 类重复序列和长度为 29 个碱基的 II 类重复序列。这两类重复序列均含有富含 AT 的基序，这些基序被推测代表启动子。在本研究中，将 9 个 IR 克隆到报告基因的上游，所有克隆均显示出启动子活性，为之前的推测提供了实验证据。比较基因组学显示，IR 序列及其相对基因组位置在同一病毒属的其他成员中高度保守。通过逆转录-聚合酶链反应（RT-PCR）方法检测到 HF2 的转录，结果表明产生了非常长的转录本，这些转录本覆盖了基因组的大部分区域，并且来自两条链。存在长的反义转录本表明存在调节作用或可能存在未被识别的编码潜力。
