SUMMARY: This article summarizes what we know about ciliate epigenetics so far. The first section is an introduction to their weird nucleus situation: ciliates have two types of nuclei, the macronucleus and the micronucleus. Several examples of ciliate epigenetics are given in sections 2 and 3. Some morphological changes that can occur include surface proteins that are expressed based on the environment and the state of the cytoplasm. Double mouths and cirri are formed when some ciliates are exposed to heat and these traits are then passed on to daughter cells, despite being acquired as a response to the environment. Non-mendelian mating is another example of epigenetic changes. On the molecular level (in the 3rd section), epigenetic changes occur when RNA is used to delete certain parts of the macronucleus or unscramble parts that are not in the right order. The conclusion of the article talks about the similarities between these epigenetic methods to methods used to stop transposons.
LESSON COMMENTS: Students will need to have a solid understanding of mitosis and meiosis before reading this article. The information in this article deviates from what is considered to be “standard” biology, but it is nonetheless, important for students to see that the biology they study in textbooks is only for a narrow range of organisms. From the difference in the number and function of nuclei to the different types of RNA, this article is best suited for Advanced Biology students or students doing research.
Pilling, O. A., Rogers, A. J., Gulla-Devaney, B., & Katz, L. A. (2017). Insights into transgenerational epigenetics from studies of ciliates. European journal of protistology, 61(Pt B), 366-375.