在灵长类隐形病毒中,使用子和氨基酸组成的不同模式
Angelo Pavesi1, Fabio Romerio2
1Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy.
Viruses
|July 29, 2023
概括
人类免疫缺陷病毒1型 (HIV-1) 呈现出明显的编码使用,这表明自然选择可能会影响其遗传构成. 这种偏见与单细胞基因表达相关,可能解释病毒储存库.
科学领域:
- 病毒学 病毒学
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 哺乳动物的lentiviruses,包括人类免疫缺陷病毒1型 (HIV-1),拥有RNA基因组与高腺素和低细胞因子含量.
- 与宿主基因组相比,这种偏向的核酸组成会产生不同的同义代码子频率.
- 了解这些差异对于理解病毒复制和病变产生至关重要.
研究的目的:
- 为了研究灵长类lentiviruses中的codon和氨基酸组成差异.
- 确定HIV-1编码子的使用是否反映了适应特定宿主细胞类型的情况.
主要方法:
- 组装了一个灵长类林氏病毒基因组序列 (SIV,HIV-2,HIV-1) 的数据集.
- 使用主要成分分析来分析子和氨基酸组成.
- 与人类单细胞,B细胞和T淋巴细胞的基因表达模式相关联的HIV-1编码子使用.
主要成果:
- 艾滋病毒-1 显示在同义码子第三位的腺因和胆氨酸显著丰富.
- 在非同义的第一个和第二个编码子位置观察到腺因和关氨酸的丰富,影响蛋白质组成.
- 艾滋病毒-1编码子使用与单细胞表达的基因有很强的相关性,超过了与淋巴细胞的相关性.
结论:
- 自然选择似乎在HIV-1中塑造了编码子的使用.
- 观察到的编码子偏差可能表明适应宿主细胞环境,特别是单细胞.
- 这一发现提供了关于HIV-1存储库在单细胞中的建立和维护的见解.
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