How mothers predict the future: epigenetics and environment

突如其来的环境变化对许多生物的生存构成了挑战。一些生物进化出了应对不确定性的机制，通过感知环境并将选定的适应性特征传递给下一代。我们以线虫Auanema freiburgensis为模型，研究了母体感受到的环境信号导致种系发生改变以产生抗逆后代的机制。在这种线虫中，同一物种的线虫产生的化学物质被用作过度拥挤的信号。因此，通过感知这些化学物质，母亲为后代“做好了准备”，以承受在过度拥挤的条件下出现的食物缺乏。后代以幼虫的形式停止发育，并能在没有食物的情况下存活几个月。一旦处于良好的环境中，幼虫就会恢复发育，成为自受精的成虫。该项目的主要目标是确定母亲感受到的化学性质，感觉神经元如何将信息传递到性腺，以及生殖系变化如何导致不同类型的后代。

Sudden environmental changes are challenging for the survival of many organisms. Some organisms evolved mechanisms to cope with uncertainty, by sensing the environment and transmitting selected adaptive traits to the next generation. We use the nematode Auanema freiburgensis as model to study the mechanisms by which environmental signals sensed by the mother results in the modification of the germline to produce stress-resistant progeny. In this nematode, chemicals produced by nematodes of the same species are used as signals for overcrowding. Thus, by sensing these chemicals, the mother 'prepares' the progeny to withstand the lack of food that occurs in overcrowded conditions. The progeny arrests development in the form of larvae, and can survive in the absence of food for several months. Once in a benign environment, the larvae resume development to become self-fertilizing adults. The main objectives of the project are to identify the chemical nature sensed by the mothers, how the sensory neurons convey the information to the gonad, and how the germline changes result in different kinds of progeny.