Department of Molecular Biosciences, The Wenner-Gren Institute
New Function Uncovered: a Non-Coding RNA is Required for Antiviral Defence
Recent research published in Nucleic Acids Research has uncovered a novel role for small nucleolar RNAs (snoRNAs) in the transcriptional regulation of the anti-viral response. Traditionally, snoRNAs are known for their role in ribosomal biogenesis. Here, the Visa group at the Department of Molecular Biosciences, Wenner-Gren Institute (MBW) at Stockholm University, in collaboration with researchers from various Swedish universities, has demonstrated that snoRNAs also participate in the regulating chromatin accessibility to influence gene transcription profiles.
In this study, the fruit fly Drosophila melanogaster was used as a model organism to investigate the regulation of immune responses. When fruit flies are infected with viruses, the host’s cellular machinery is activated, which triggers an effective immune response. U3 small nucleolar RNA (U3 snoRNA) is one of the genes induced during this process. The induced U3 snoRNA helps maintain an open chromatin conformation, thereby facilitating the transcription of various immune pathway genes. U3 snoRNA acts by recruiting the SWI/SNF chromatin remodeler, Brahma, to immune genes. If U3 snoRNA is knocked out, fruit fly larvae fail to efficiently fight viral infections and die during late larval development. Not only does U3 snoRNA facilitate immune gene activation, but it also promotes the chromatin remodelling needed for immune gene expression, establishing it as a key regulator of the antiviral response.
Proposed model for the role of a snoRNA in the activation of antiviral response genes.
“The study reveals an unexpected layer of regulatory complexity in innate immunity and expands the functional repertoire of U3 snoRNA”, says Dr. Shruti Jain, researcher at MBW and main author of the study.
Our research aims at understanding the mechanisms by which RNA and RNA degradation by the exosome contribute to chromatin regulation, gene expression and genome integrity.
We study gene expression with a focus on the role of POU/Oct transcription factors in development, stem cell regulation, cancer and immunity. We use the fruitfly Drosophila as a model organism and utilize the genetic tools developed for this organism, in combination with high-throughput expression analyses, high resolution microscopy and live-cell imaging.
The immune system that kills disease-causing microbes and heals tissues, and the DNA repair system that maintains gene expression are essential for life. However, they require careful regulation to prevent the destruction of own tissues. The goal of my research is to better understand these systems and find new strategies in the treatment of diseases.
