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阴影下:老年偏见的基因在组织和细胞类型特定水平上都受到弱净化选择

Nisan Yıldız¹, Hamit İzgi¹, Firuza Rahimova¹

¹Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey.

Genome biology and evolution

|October 15, 2025

概括

削弱的净化选择驱动有害基因变异随着年龄的增长而积累,从而导致衰老. 这项研究证实了不同物种老化组织中的基因保护减少,支持突变积累假说.

科学领域:

进化生物学进化生物学
遗传学是一个遗传学.
老年学是一门学科.

背景情况:

突变积累假设认为,老年人减少净化选择会导致晚期起作用的有害变体的积累.
之前的研究表明,与哺乳动物和昆虫的年轻偏差基因相比,老偏差基因的序列保护能力较弱.
关于组织组成变化的作用与细胞自主变化的作用以及对非哺乳动物物种的适用性仍然存在不确定性.

研究的目的:

为了研究与年龄相关的转录组保护的普遍性,在多种多元动物类别中进行.
为了确定这种趋势是否是由细胞自主表达变化或组织组成变化驱动的.
在衰老过程中检查单细胞类型水平上的转录组保护模式.

主要方法:

分析了6个数据集中的5种物种的大量组织和细胞类型特定RNA测序数据.
在各种组织和细胞类型中,比较老偏差和年轻偏差基因之间的序列保存.
包括非哺乳动物脊椎动物 (,鱼) 和无脊椎动物 (果) 的数据,以及小鼠的数据.

主要成果:

与年龄相关的转录组保护的减少在非哺乳动物物种的老化组织中普遍存在,包括脊椎动物和无脊椎动物.
这一趋势在成年小鼠的单细胞类型水平上,在多种组织 (肺,大脑,肝脏,肌肉,脏,皮肤) 中观察到.
在大多数分析的细胞类型中,老偏差基因的保存率降低,包括组织特异性和无处不在的免疫细胞.

结论:

这些发现表明,与年龄相关的转录组保护下降是超动物中普遍存在的现象.
结果支持细胞自主表达变化的作用驱动这种模式,而不是仅仅是组织组成的变化.
这项研究强化了突变积累过程作为塑造元动物衰老的重要因素.

关键词:

细胞类型组成细胞类型组成老龄化过程的演变.突变的积累是突变的积累.选择阴影的选择一个单细胞的单细胞.转录组学转录组学是指转录组学.

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