通过双重内部核糖体入口点提高循环RNA翻译效率
Yawen Sun1, Yimin Zhang2, Weijie Chen2
1College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China.
Biology
|February 26, 2026
概括
循环RNAs (circRNAs) 提供稳定的药物输送. 双内部核糖体进入部位 (IRES) 策略提高了circRNA的翻译效率,克服了治疗应用上限独立表达的局限性.
科学领域:
- 生物技术是生物技术.
- 分子生物学分子生物学
- 药物输送系统 药物输送系统
背景情况:
- 循环RNA (circRNA) 是一种稳定,非编码的RNA分子,具有作为药物输送载体的潜力.
- circRNAs缺乏5'盖,依赖于内部核糖体进入点 (IRES) 来启动翻译,这比依赖盖的翻译效率低.
- 增强circRNA翻译对于最大限度地提高其治疗疗效至关重要.
研究的目的:
- 开发一种提高circRNA翻译效率的策略.
- 为了研究双IRES系统对circRNAs的cap-independent翻译的有效性.
- 为了确定最佳的IRES元素,以改善circRNA表达.
主要方法:
- 设计和制造了采用双IRES策略的circRNA分子.
- 测试了各种IRES元素,重点关注来自脑肌心炎病毒 (EMCV) 家族的元素.
- 评估了不同IRES组合的工程circRNAs的翻译活性和表达水平.
主要成果:
- 与单个IRES元素相比,双IRES策略显著增强了circRNA翻译.
- 来自EMCV的IRES元素,特别是当与5'IRES协调在编码序列 (CDS) 的3'放置时,显示出最佳增强.
- 确定的双IRES组合与多个编码序列兼容.
结论:
- 双IRES策略是促进circRNA转化的一种有效方法.
- 这种方法克服了circRNAs中cap独立翻译的固有局限性.
- 这些发现为开发增强的基于circRNA的疗法和输送系统提供了有价值的工具.
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