Spadafora Corrado
Institute of Translational Pharmacology, National Research Council (CNR), 100 Via del Fosso del Cavaliere, 00133 Rome, Italy.
Environ Epigenet. 2020 Jul 18;6(1):dvaa009. doi: 10.1093/eep/dvaa009. eCollection 2020 Jan.
The notion that epigenetic information can be transmitted across generations is supported by mounting waves of data, but the underlying mechanisms remain elusive. Here, a model is proposed which combines different lines of experimental evidence. First, it has been shown that somatic tissues exposed to stressing stimuli release circulating RNA-containing extracellular vesicles; second, epididymal spermatozoa can take up, internalize and deliver the RNA-containing extracellular vesicles to oocytes at fertilization; third, early embryos can process RNA-based information. These elements constitute the building blocks upon which the model is built. The model proposes that a continuous stream of epigenetic information flows from parental somatic tissues to the developing embryos. The flow can cross the Weismann barrier, is mediated by circulating vesicles and epididymal spermatozoa, and has the potential to generate epigenetic traits that are then stably acquired in the offspring. In a broader perspective, it emerges that a natural 'assembly line' operates continuously, aiming at passing the parental epigenetic blueprint in growing embryos.
表观遗传信息能够跨代传递这一观点得到了越来越多数据的支持，但其潜在机制仍然难以捉摸。在此，我们提出了一个整合了不同实验证据的模型。首先，研究表明，暴露于应激刺激下的体细胞会释放含RNA的细胞外囊泡；其次，附睾精子能够摄取、内化含RNA的细胞外囊泡，并在受精时将其传递给卵母细胞；第三，早期胚胎能够处理基于RNA的信息。这些要素构成了构建该模型的基石。该模型提出，表观遗传信息的连续流从亲本体细胞组织流向发育中的胚胎。这种信息流能够跨越魏斯曼屏障，由循环囊泡和附睾精子介导，并有可能产生表观遗传特征，这些特征随后会在后代中稳定获得。从更广泛的角度来看，一条自然的“装配线”在持续运作，旨在将亲本表观遗传蓝图传递给发育中的胚胎。
