科學家發現線蟲跨代小RNA遺傳的三個原理
作者:
小柯機器人發布時間:2020/8/26 13:39:54
以色列特拉維夫大學Oded Rechavi、Leah Houri-Zeevi等研究人員合作發現可解釋線蟲跨代小RNA遺傳的三個原理。相關論文於2020年8月24日在線發表在《細胞》雜誌上。
研究人員發現,同基因個體在跨代反應的持久性方面存在顯著差異。通過檢查超過20,000種線蟲的譜系,研究人員發現了三個原理:(1)每個母親起始的沉默在其後代之間平均分配;可遺傳的RNAi會消散,但每一代都是統一的。(2)譜系之間的差異之所以出現,是因為起始遺傳反應的母親隨機地承擔著決定後代命運的不同「繼承狀態」。(3)RNAi應答繼續被繼承的可能性越大,持續的世代就越多。遺傳狀態由HSF-1確定,其調節沉默因子並因此調節小RNA水平。
研究人員發現,基於父母的繼承狀態,後代應對壓力的發育速度可以被預測。
據了解,在線蟲中,經驗能夠觸發隔代的小RNA的反應。專屬機制可確保遺傳效應的重置,但這些響應如何在群體中分離是未知的。
附:英文原文
Title: Three Rules Explain Transgenerational Small RNA Inheritance in C. elegans
Author: Leah Houri-Zeevi, Yael Korem Kohanim, Olga Antonova, Oded Rechavi
Issue&Volume: 2020-08-24
Abstract: Experiences trigger transgenerational small RNA-based responses in C. elegans nematodes. Dedicated machinery ensures that heritable effects are reset, but how the responses segregate in the population is unknown. We show that isogenic individuals differ dramatically in the persistence of transgenerational responses. By examining lineages of more than 20,000 worms, three principles emerge: (1) The silencing each mother initiates is distributed evenly among her descendants; heritable RNAi dissipates but is uniform in every generation. (2) Differences between lineages arise because the mothers that initiate heritable responses stochastically assume different 「inheritance states」 that determine the progeny’s fate. (3) The likelihood that an RNAi response would continue to be inherited increases the more generations it lasts. The inheritance states are determined by HSF-1, which regulates silencing factors and, accordingly, small RNA levels. We found that, based on the parents』 inheritance state, the descendants』 developmental rate in response to stress can be predicted.
DOI: 10.1016/j.cell.2020.07.022
Source: https://www.cell.com/cell/fulltext/S0092-8674(20)30930-2
Cell:《細胞》,創刊於1974年。隸屬於細胞出版社,最新IF:36.216