Next Article in Journal
Genome-Wide Identification of circRNAs in Pathogenic Basidiomycetous Yeast Cryptococcus neoformans Suggests Conserved circRNA Host Genes over Kingdoms
Previous Article in Journal
In a quest for engineering acidophiles for biomining applications: challenges and opportunities
Article Menu
Issue 2 (February) cover image

Export Article

Open AccessBrief Report
Genes 2018, 9(2), 117;

Environmental Temperature Controls Accumulation of Transacting siRNAs Involved in Heterochromatin Formation

Molecular Cell Dynamics, Centre for Human and Molecular Biology, Saarland University, 66123 Saarbrücken, Germany
Cluster of Excellence, Multimodal Computing and Interaction, Saarland University and Department for Computational Biology and Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics Campus, 66123 Saarbrücken, Germany
Genetics/Epigenetics, Centre for Human and Molecular Biology, Saarland University, 66123 Saarbrücken, Germany
Current address: Molecular Cell Biology and Microbiology, Wuppertal University, Gausstraße 20, V.12.070, 42097 Wuppertal, Germany
These authors contributed equally to this work.
Author to whom correspondence should be addressed.
Received: 4 January 2018 / Revised: 6 February 2018 / Accepted: 12 February 2018 / Published: 21 February 2018
(This article belongs to the Section Population and Evolutionary Genetics and Genomics)
Full-Text   |   PDF [1662 KB, uploaded 24 February 2018]   |  


Genes or alleles can interact by small RNAs in a homology dependent manner meaning that short interfering (siRNAs) can act in trans at the chromatin level producing stable and heritable silencing phenotypes. Because of the puzzling data on endogenous paramutations, their impact contributing to adaptive evolution in a Lamarckian manner remains unknown. An increasing number of studies characterizes the underlying siRNA accumulation pathways using transgene experiments. Also in the ciliate Paramecium tetraurelia, we induce trans silencing on the chromatin level by injection of truncated transgenes. Here, we characterize the efficiency of this mechanism at different temperatures showing that silencing of the endogenous genes is temperature dependent. Analyzing different transgene constructs at different copy numbers, we dissected whether silencing efficiency is due to varying precursor RNAs or siRNA accumulation. Our data shows that silencing efficiency correlates with more efficient accumulation of primary siRNAs at higher temperatures rather than higher expression of precursor RNAs. Due to higher primary levels, secondary siRNAs also show temperature dependency and interestingly increase their relative proportion to primary siRNAs. Our data shows that efficient trans silencing on the chromatin level in P. tetraurelia depends on environmental parameters, thus being an important epigenetic factor limiting regulatory effects of siRNAs. View Full-Text
Keywords: RNA interference; transitivity; chromatin; environment RNA interference; transitivity; chromatin; environment

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary material


Share & Cite This Article

MDPI and ACS Style

Pirritano, M.; Götz, U.; Karunanithi, S.; Nordström, K.; Schulz, M.H.; Simon, M. Environmental Temperature Controls Accumulation of Transacting siRNAs Involved in Heterochromatin Formation. Genes 2018, 9, 117.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Genes EISSN 2073-4425 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top