哺乳动物精子成熟和受精过程中的tRNA片段的生物发生和功能
Upasna Sharma1, Colin C Conine1, Jeremy M Shea1
1Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
概括
父亲的饮食通过精子小RNA影响后代的新陈代谢. 饮食中的蛋白质限制会改变精子小RNA水平,包括转移RNA片段,这些片段会调节早期胚胎中的基因表达.
科学领域:
- 表观遗传学和发育生物学
- 精子生物学和RNA调控
- 后代表型的营养编程
背景情况:
- 越来越多地认识到父母的环境会影响后代的表型.
- 父母饮食影响后代代谢的具体机制尚未完全理解.
- 精子中的小RNA被认为是这种代际影响的潜在媒介.
研究的目的:
- 通过精子小RNA研究父亲的饮食与后代代谢之间的机制联系.
- 通过父亲的饮食蛋白质限制诱导的精子sRNA组成的变化.
- 在胚胎发育中确定特定sRNA的功能作用,例如转移RNA片段.
主要方法:
- 对小鼠进行饮食蛋白质限制,以评估其对精子sRNA概况的影响.
- 在不同成熟阶段的精子中分析小RNA (sRNA),包括let-7和转移RNA (tRNA) 片段.
- 作为精子RNA有效载荷的载体,对表皮细胞进行研究.
- 使用胚胎干细胞和胚胎进行体外实验,以评估tRNA片段的功能.
主要成果:
- 父亲蛋白质限制改变了成熟精子中的sRNA水平,降低了let-7和增加了5' glycine转移RNAs (tRNAs).
- 在丸精子中稀缺的tRNA片段在膜过渡过程中增加,并在膜细胞中发现.
- 在实验室中,表皮细胞向未成熟的精子传递特定的RNA有效载荷.
- 在胚胎干细胞和胚胎中,糖氨酸tRNA片段抑制了与内源逆元MERVL相关的基因.
结论:
- 在丸后的精子成熟过程中,sRNA生物发生的饮食调节.
- 转移RNA片段在植入前胚胎中的内源逆元调节中发挥作用.
- 父亲的饮食可以通过精子携带的RNA将表观遗传信息传递给后代,从而影响胚胎的基因表达.
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